Mass killings under communist regimes

Mass killings under communist regimes occurred throughout the 20th century. Death estimates vary widely, depending on the definitions of the deaths that are included in them. Estimates account for executions, deaths from man-made and intentional famines, as well as deaths that occurred during forced labor, deportations, or imprisonment.

In addition to mass killings, terms that are used to define such killings include democide, politicide, classicide, and genocide.

Terminology and usage
Several different terms are used to describe the intentional killing of large numbers of noncombatants. According to Anton Weiss-Wendt, the field of comparative genocide studies has very "little consensus on defining principles such as definition of genocide, typology, application of a comparative method, and timeframe." According to Professor of Economics Attiat Ott, mass killing has emerged as a "more straightforward" term.

The following terminology has been used by individual authors to describe mass killings of unarmed civilians by communist governments, individually or as a whole:
 * Classicide – Professor Michael Mann has proposed classicide to mean the "intended mass killing of entire social classes." Classicide is considered "premeditated mass killing" narrower than genocide in that it targets a part of a population defined by its social status, but broader than politicide in that the group is targeted without regard to their political activity.
 * Crime against humanity – Professor Klas-Göran Karlsson uses crimes against humanity, which includes "the direct mass killings of politically undesirable elements, as well as forced deportations and forced labour." Karlsson acknowledges that the term may be misleading in the sense that the regimes targeted groups of their own citizens, but he considers it useful as a broad legal term which emphasizes attacks on civilian populations and because the offenses demean humanity as a whole. Historian Jacques Sémelin and Professor Michael Mann believe that crime against humanity is more appropriate than genocide or politicide when speaking of violence by communist regimes. See also: Crimes against humanity under communist regimes.
 * Democide – Professor Rudolph Rummel defined democide as "the intentional killing of an unarmed or disarmed person by government agents acting in their authoritative capacity and pursuant to government policy or high command." His definition covers a wide range of deaths, including forced labor and concentration camp victims; killings by "unofficial" private groups; extrajudicial summary killings; and mass deaths due to the governmental acts of criminal omission and neglect, such as in deliberate famines as well as killings by de facto governments, such as warlords or rebels in a civil war. This definition covers any murder of any number of persons by any government, and it has been applied to killings that were perpetrated by communist regimes.
 * Genocide – Under the Genocide Convention, the crime of genocide generally applies to the mass murder of ethnic rather than political or social groups. The clause which granted protection to political groups was eliminated from the United Nations resolution after a second vote because many states, including the Soviet Union under Joseph Stalin, feared that it could be used to impose unneeded limitations on their right to suppress internal disturbances. Scholarly studies of genocide usually acknowledge the UN's omission of economic and political groups and use mass political killing datasets of democide and genocide and politicide or geno-politicide. The killings that were committed by the Khmer Rouge in Cambodia has been labeled a genocide or an auto-genocide; and the deaths that occurred under Leninism and Stalinism in the Soviet Union, as well as those that occurred under Maoism in China, have been controversially investigated as possible cases. In particular, the Soviet famine of 1932–1933 and the Great Chinese Famine, which occurred during the Great Leap Forward, have both been "depicted as instances of mass killing underpinned by genocidal intent."
 * Holocaust – communist holocaust has been used by some state officials and non-governmental organizations. The similar term red Holocaust—coined by the Munich Institut für Zeitgeschichte—has been used by Professor Steven Rosefielde for communist "peacetime state killings," while stating that it "could be defined to include all murders (judicially sanctioned terror-executions), criminal manslaughter (lethal forced labor and ethnic cleansing), and felonious negligent homicide (terror-starvation) incurred from insurrectionary actions and civil wars prior to state seizure, and all subsequent felonious state killings." According to Jörg Hackmann, this term is not popular among scholars in Germany or internationally. Alexandra Laignel-Lavastine writes that usage of this term "allows the reality it describes to immediately attain, in the Western mind, a status equal to that of the extermination of the Jews by the Nazi regime." Michael Shafir writes that the use of the term supports the "competitive martyrdom component of Double Genocide", a theory whose worst version is Holocaust obfuscation. George Voicu states that Leon Volovici has "rightfully condemned the abusive use of this concept as an attempt to 'usurp' and undermine a symbol specific to the history of European Jews."
 * Mass killing – Professor Ervin Staub defined mass killing as "killing members of a group without the intention to eliminate the whole group or killing large numbers of people without a precise definition of group membership. In a mass killing the number of people killed is usually smaller than in genocide." Referencing earlier definitions, Professors Joan Esteban, Massimo Morelli, and Dominic Rohner have defined mass killings as "the killings of substantial numbers of human beings, when not in the course of military action against the military forces of an avowed enemy, under the conditions of the essential defenselessness and helplessness of the victims." The term has been defined by Professor Benjamin Valentino as "the intentional killing of a massive number of noncombatants", where a "massive number" is defined as at least 50,000 intentional deaths over the course of five years or less. This is the most accepted quantitative minimum threshold for the term. He applied this definition to the cases of Stalin's Soviet Union, China under Mao Zedong and Cambodia under the Khmer Rouge while admitting that "mass killings on a smaller scale" also appear to have been carried out by regimes in North Korea, Vietnam, Eastern Europe and various nations in Africa. Alongside Valentino, Jay Ulfelder has used a threshold of 1,000 killed. Alex Bellamy states that 14 of the 38 instances of "mass killing since 1945 perpetrated by non-democratic states outside the context of war" were by communist governments. Professors Frank Wayman and Atsushi Tago used mass killing from Valentino and concluded that even with a lower threshold (10,000 killed per year, 1,000 killed per year, or even 1 killed per year) "autocratic regimes, especially communist, are prone to mass killing generically, but not so strongly inclined (i.e. not statistically significantly inclined) toward geno-politicide." According to Attiat F. Ott and Sang Hoo Bae, there is a general consensus that mass killing constitutes the act of intentionally killing a number of non-combatants, but that number can range from as few as four to more than 50,000 people. Yang Su used a definition of mass killing from Valentino but allows as a "significant number" more than 10 killed in one day in one town. He used collective killing for analysis of mass killing in areas smaller than a whole country that may not meet Valentino's threshold.
 * Politicide – the term is used to describe the killing of groups that would not otherwise be covered by the Genocide Convention. Professor Barbara Harff studies genocide and politicide—sometimes shortened as geno-politicide—in order to include the killing of political, economic, ethnic and cultural groups. Professor Manus I. Midlarsky uses politicide to describe an arc of large-scale killing from the western parts of the Soviet Union to China and Cambodia. In his book The Killing Trap: Genocide in the Twentieth Century, Midlarsky raises similarities between the killings of Stalin and Pol Pot.
 * Repression – Professor Stephen Wheatcroft comments that in the case of the Soviet Union terms such as the terror, the purges, and repression are used to refer to the same events. He believes the most neutral terms are repression and mass killings, although in Russian the broad concept of repression is commonly held to include mass killings and it is sometimes assumed to be synonymous with it, which is not the case in other languages.

Estimates
According to professor of history Klas-Göran Karlsson, discussion of the number of victims of communist regimes has been "extremely extensive and ideologically biased." Political scientist Rudolph Rummel and historian Mark Bradley have written that, while the exact numbers have been in dispute, the order of magnitude is not. Rummel and other genocide scholars are focused primarily on establishing patterns and testing various theoretical explanations of genocides and mass killings. In their work, as they are dealing with large data sets that describe mass mortality events globally, they have to rely on selective data provided by country experts, so precise estimates are neither a required nor expected result of their work.

Any attempt to estimate a total number of killings under communist regimes depends greatly on definitions, and the idea to group together different countries such as Afghanistan and Hungary has no adequate explanation. During the Cold War era, some authors (Todd Culberston), dissidents (Aleksandr Solzhenitsyn), and anti-communists in general have attempted to make both country-specific and global estimates, although they were mostly unreliable and inflated, as shown by the 1990s and beyond. Scholars of communism have mainly focused on individual countries, and genocide scholars have attempted to provide a more global perspective, while maintaining that their goal is not reliability but establishing patterns. Scholars of communism have debated on estimates for the Soviet Union, not for all communist regimes, an attempt which was popularized by the introduction to The Black Book of Communism and was controversial. Among them, Soviet specialists Michael Ellman and J. Arch Getty have criticized the estimates for relying on émigre sources, hearsay, and rumor as evidence, and cautioned that historians should instead utilize archive material. Such scholars distinguish between historians who base their research on archive materials, and those whose estimates are based on witnesses evidence and other data that is unreliable. Soviet specialist Stephen G. Wheatcroft says that historians relied on Solzhenitsyn to support their higher estimates but research in the state archives vindicated the lower estimates, while adding that the popular press has continued to include serious errors that should not be cited, or relied on, in academia. Rummel was also another widely used and cited source but not reliable about estimates.

Notable estimate attempts include the following:
 * In 1978, journalist Todd Culbertson wrote an article in The Richmond News Leader, republished in Human Events, in which he stated that "[a]vailable evidence indicates that perhaps 100 million persons have been destroyed by the Communists; the imperviousness of the Iron and Bamboo curtains prevents a more definitive figure."
 * In 1985, John Lenczowski, director of European and Soviet Affairs at the United States National Security Council, wrote an article in The Christian Science Monitor in which he stated that the "number of people murdered by communist regimes is estimated at between 60 million and 150 million, with the higher figure probably more accurate in light of recent scholarship."
 * In 1993, Zbigniew Brzezinski, former National Security Advisor to Jimmy Carter, wrote that "the failed effort to build communism in the twentieth century consumed the lives of almost 60,000,000."
 * In 1994, Rummel's book Death by Government included about 110 million people, foreign and domestic, killed by communist democide from 1900 to 1987. This total did not include deaths from the Great Chinese Famine of 1958–1961 due to Rummel's then belief that "although Mao's policies were responsible for the famine, he was mislead about it, and finally when he found out, he stopped it and changed his policies." In 2004, historian Tomislav Dulić criticized Rummel's estimate of the number killed in Tito's Yugoslavia as an overestimation based on the inclusion of low-quality sources, and stated that Rummel's other estimates may suffer from the same problem if he used similar sources for them. Rummel responded with a critique of Dulić's analysis but was not convincing. In 2005, a retired Rummel revised upward his total for communist democide between 1900 and 1999 from 110 million to about 148 million due to additional information about Mao's culpability in the Great Chinese Famine from Mao: The Unknown Story, including Jon Halliday and Jung Chang's estimated 38 million famine deaths. Karlsson describes Rummel's estimates as being on the fringe, stating that "they are hardly an example of a serious and empirically-based writing of history", and mainly discusses them "on the basis of the interest in him in the blogosphere."
 * In 1997, historian Stéphane Courtois's introduction to The Black Book of Communism, an impactful yet controversial work written about the history of communism in the 20th century, gave a "rough approximation, based on unofficial estimates" approaching 100 million killed. The subtotals listed by Courtois added up to 94.36 million killed. Nicolas Werth and Jean-Louis Margolin, contributing authors to the book, criticized Courtois as obsessed with reaching a 100 million overall total. In his foreword to the 1999 English edition, Martin Malia wrote that "a grand total of victims variously estimated by contributors to the volume at between 85 million and 100 million." Courtois' attempt to equate Nazism and communist regimes was controversial, and remains on the fringes, on both scientific and moral grounds.
 * In 2005, associate professor Benjamin Valentino stated that the number of non-combatants killed by communist regimes in the Soviet Union, China, and Cambodia alone ranged from a low of 21 million to a high of 70 million. Citing Rummel and others, Valentino wrote that the "highest end of the plausible range of deaths attributed to communist regimes" was up to 110 million."
 * In 2010, professor of economics Steven Rosefielde wrote in Red Holocaust that the internal contradictions of communist regimes caused the killing of approximately 60 million people and perhaps tens of millions more.
 * In 2011, self-described atrocitiologist Matthew White published his rough total of 70 million "people who died under communist regimes from execution, labor camps, famine, ethnic cleansing, and desperate flight in leaky boats", not counting those killed in wars.
 * In 2012, academic Alex J. Bellamy wrote that a "conservative estimate puts the total number of civilians deliberately killed by communists after the Second World War between 6.7 million and 15.5 million people, with the true figure probably much higher."
 * In 2014, professor of Chinese politics Julia Strauss wrote that while there was the beginning of a scholarly consensus on figures of around 20 million killed in the Soviet Union and 2–3 million in Cambodia, there was no such consensus on numbers for China.
 * In 2016, the Dissident blog of the Victims of Communism Memorial Foundation made an effort to compile ranges of estimates using sources from 1976 to 2010, and wrote that the overall range "spans from 42,870,000 to 161,990,000" killed, with 100 million the most commonly cited figure.
 * In 2017, historian Stephen Kotkin wrote in The Wall Street Journal that communist regimes killed at least 65 million people between 1917 and 2017, commenting: "Though communism has killed huge numbers of people intentionally, even more of its victims have died from starvation as a result of its cruel projects of social engineering."

Criticism is mostly focused on three aspects, namely that the estimates are based on sparse and incomplete data when significant errors are inevitable, the figures are skewed to higher possible values, and victims of civil wars, Holodomor, and other famines, and wars involving communist governments should not be counted. Criticism of the high-end estimates such as Rummel's have focused on two aspects, namely his choice of data sources and his statistical approach. Historical sources Rummel based his estimates upon can rarely serve as sources of reliable figures. The statistical approach Rummel used to analyze big sets of diverse estimates may lead to dilution of useful data with noisy ones.

Another common criticism, as articulated by anthropologist and former European communist regimes specialist Kristen Ghodsee and other scholars, is that the body-counting reflects an anti-communist point of view and is mainly approached by anti-communist scholars, and is part of the popular "victims of communism" narrative, with 100 million being the most common, popularly used estimate, which is used not only to discredit the communist movement but the whole political left. Anti-communist organizations seek to institutionalize the "victims of communism" narrative as a double genocide theory, or the moral equivalence between the Nazi Holocaust (race murder) and those killed by communist regimes (class murder). Alongside philosopher Scott Sehon, Ghodsee wrote that "quibbling about numbers is unseemly. What matters is that many, many people were killed by communist regimes." The same body-counting can be easily applied to other ideologies or systems, such as capitalism.

Ideology
Klas-Göran Karlsson writes: "Ideologies are systems of ideas, which cannot commit crimes independently. However, individuals, collectives and states that have defined themselves as communist have committed crimes in the name of communist ideology, or without naming communism as the direct source of motivation for their crimes." Academics such as Daniel Goldhagen, Richard Pipes, and John Gray have written books about communist regimes for a popular audience, and scholars such as Rudolph Rummel consider the ideology of communism to be a significant causative factor in mass killings. In the introduction to The Black Book of Communism, Stéphane Courtois claims an association between communism and criminality, stating that "Communist regimes ... turned mass crime into a full-blown system of government", while adding that this criminality lies at the level of ideology rather than state practice.

Professor Mark Bradley writes that communist theory and practice has often been in tension with human rights and most communist states followed the lead of Karl Marx in rejecting "Enlightenment-era inalienable individual political and civil rights" in favor of "collective economic and social rights." Christopher J. Finlay posits that Marxism legitimates violence without any clear limiting principle because it rejects moral and ethical norms as constructs of the dominant class, and states that "it would be conceivable for revolutionaries to commit atrocious crimes in bringing about a socialist system, with the belief that their crimes will be retroactively absolved by the new system of ethics put in place by the proletariat." Rustam Singh states that Marx had alluded to the possibility of peaceful revolution; after the failed Revolutions of 1848, Singh states that Marx emphasized the need for violent revolution and revolutionary terror.

Literary historian George Watson cited an 1849 article written by Friedrich Engels called "The Hungarian Struggle" and published in Marx's journal Neue Rheinische Zeitung, stating that the writings of Engels and others show that "the Marxist theory of history required and demanded genocide for reasons implicit in its claim that feudalism, which in advanced nations was already giving place to capitalism, must in its turn be superseded by socialism. Entire nations would be left behind after a workers' revolution, feudal remnants in a socialist age, and since they could not advance two steps at a time, they would have to be killed. They were racial trash, as Engels called them, and fit only for the dung-heap of history." Watson's claims have been criticized for dubious evidence by Robert Grant, who commented that "what Marx and Engels are calling for is ... at the very least a kind of cultural genocide; but it is not obvious, at least from Watson's citations, that actual mass killing, rather than (to use their phraseology) mere 'absorption' or 'assimilation', is in question." Talking about Engels' 1849 article, historian Andrzej Walicki states: "It is difficult to deny that this was an outright call for genocide." Jean-François Revel writes that Joseph Stalin recommended study of the 1849 Engels article in his 1924 book On Lenin and Leninism.

According to Rummel, the killings committed by communist regimes can best be explained as the result of the marriage between absolute power and the absolutist ideology of Marxism. Rummel states that "communism was like a fanatical religion. It had its revealed text and its chief interpreters. It had its priests and their ritualistic prose with all the answers. It had a heaven, and the proper behavior to reach it. It had its appeal to faith. And it had its crusades against nonbelievers. What made this secular religion so utterly lethal was its seizure of all the state's instruments of force and coercion and their immediate use to destroy or control all independent sources of power, such as the church, the professions, private businesses, schools, and the family." Rummels writes that Marxist communists saw the construction of their utopia as "though a war on poverty, exploitation, imperialism and inequality. And for the greater good, as in a real war, people are killed. And, thus, this war for the communist utopia had its necessary enemy casualties, the clergy, bourgeoisie, capitalists, wreckers, counterrevolutionaries, rightists, tyrants, rich, landlords, and noncombatants that unfortunately got caught in the battle. In a war millions may die, but the cause may be well justified, as in the defeat of Hitler and an utterly racist Nazism. And to many communists, the cause of a communist utopia was such as to justify all the deaths."

Benjamin Valentino writes that "apparently high levels of political support for murderous regimes and leaders should not automatically be equated with support for mass killing itself. Individuals are capable of supporting violent regimes or leaders while remaining indifferent or even opposed to specific policies that these regimes and carried out." Valentino quotes Vladimir Brovkin as saying that "a vote for the Bolsheviks in 1917 was not a vote for Red Terror or even a vote for a dictatorship of the proletariat." According to Valentino, such strategies were so violent because they economically dispossess large numbers of people, commenting: "Social transformations of this speed and magnitude have been associated with mass killing for two primary reasons. First, the massive social dislocations produced by such changes have often led to economic collapse, epidemics, and, most important, widespread famines. ... The second reason that communist regimes bent on the radical transformation of society have been linked to mass killing is that the revolutionary changes they have pursued have clashed inexorably with the fundamental interests of large segments of their populations. Few people have proved willing to accept such far-reaching sacrifices without intense levels of coercion." According to Jacques Sémelin, "communist systems emerging in the twentieth century ended up destroying their own populations, not because they planned to annihilate them as such, but because they aimed to restructure the 'social body' from top to bottom, even if that meant purging it and recarving it to suit their new Promethean political imaginaire."

Daniel Chirot and Clark McCauley write that, especially in Joseph Stalin's Soviet Union, Mao Zedong's China, and Pol Pot's Cambodia, a fanatical certainty that socialism could be made to work motivated communist leaders in "the ruthless dehumanization of their enemies, who could be suppressed because they were 'objectively' and 'historically' wrong. Furthermore, if events did not work out as they were supposed to, then that was because class enemies, foreign spies and saboteurs, or worst of all, internal traitors were wrecking the plan. Under no circumstances could it be admitted that the vision itself might be unworkable, because that meant capitulation to the forces of reaction." Michael Mann writes that communist party members were "ideologically driven, believing that in order to create a new socialist society, they must lead in socialist zeal. Killings were often popular, the rank-and-file as keen to exceed killing quotas as production quotas." According to Vladimir Tismăneanu, "the Communist project, in such countries as the USSR, China, Cuba, Romania, or Albania, was based precisely on the conviction that certain social groups were irretrievably alien and deservedly murdered." Alex Bellamy writes that "communism's ideology of selective extermination" of target groups was first developed and applied by Joseph Stalin but that "each of the communist regimes that massacred large numbers of civilians during the Cold War developed their own distinctive account", while Steven T. Katz states that distinctions based on class and nationality, stigmatized and stereotyped in various ways, created an "otherness" for victims of communist rule that was important for legitimating oppression and death. Martin Shaw writes that "nationalist ideas were at the heart of many mass killings by Communist states", beginning with Stalin's "new nationalist doctrine of 'socialism in one country'", and killing by revolutionary movements in the Third World was done in the name of national liberation.

Political system
Anne Applebaum writes that "without exception, the Leninist belief in the one-party state was and is characteristic of every communist regime" and "the Bolshevik use of violence was repeated in every communist revolution." Phrases said by Vladimir Lenin and Cheka founder Felix Dzerzhinsky were deployed all over the world. Applebaum states that as late as 1976, Mengistu Haile Mariam unleashed a Red Terror in Ethiopia. To his colleagues in the Bolshevik government, Lenin was quoted as saying: "If we are not ready to shoot a saboteur and White Guardist, what sort of revolution is that?"

Robert Conquest stressed that Stalin's purges were not contrary to the principles of Leninism but rather a natural consequence of the system established by Lenin, who personally ordered the killing of local groups of class enemy hostages. Alexander Nikolaevich Yakovlev, architect of perestroika and glasnost and later head of the Presidential Commission for the Victims of Political Repression, elaborates on this point, stating: "The truth is that in punitive operations Stalin did not think up anything that was not there under Lenin: executions, hostage taking, concentration camps, and all the rest." Historian Robert Gellately concurs, commenting: "To put it another way, Stalin initiated very little that Lenin had not already introduced or previewed."

Stephen Hicks of Rockford College ascribes the violence characteristic of 20th-century socialist rule to these collectivist regimes' abandonment of protections of civil rights and rejection of the values of civil society. Hicks writes that whereas "in practice every liberal capitalist country has a solid record for being humane, for by and large respecting rights and freedoms, and for making it possible for people to put together fruitful and meaningful lives", in socialism "practice has time and again proved itself more brutal than the worst dictatorships prior to the twentieth century. Each socialist regime has collapsed into dictatorship and begun killing people on a huge scale."

Eric D. Weitz says that the mass killing in communist states is a natural consequence of the failure of the rule of law, seen commonly during periods of social upheaval in the 20th century. For both communist and non-communist mass killings, "genocides occurred at moments of extreme social crisis, often generated by the very policies of the regimes", and are not inevitable but are political decisions. Steven Rosefielde writes that communist rulers had to choose between changing course and "terror-command" and more often than not chose the latter. Michael Mann posits that a lack of institutionalized authority structures meant that a chaotic mix of both centralized control and party factionalism were factors in the killing.

Leaders
Professor Matthew Krain states that many scholars have pointed to revolutions and civil wars as providing the opportunity for radical leaders and ideologies to gain power and the preconditions for mass killing by the state. Professor Nam Kyu Kim writes that exclusionary ideologies are critical to explaining mass killing, but the organizational capabilities and individual characteristics of revolutionary leaders, including their attitudes towards risk and violence, are also important. Besides opening up political opportunities for new leaders to eliminate their political opponents, revolutions bring to power leaders who are more apt to commit large-scale acts of violence against civilians in order to legitimize and strengthen their own power. Genocide scholar Adam Jones states that the Russian Civil War was very influential on the emergence of leaders like Stalin and it also accustomed people to "harshness, cruelty, terror." Martin Malia called the "brutal conditioning" of the two World Wars important to understanding communist violence, although not its source.

Historian Helen Rappaport describes Nikolay Yezhov, the bureaucrat who was in charge of the NKVD during the Great Purge, as a physically diminutive figure of "limited intelligence" and "narrow political understanding. ... Like other instigators of mass murder throughout history, [he] compensated for his lack of physical stature with a pathological cruelty and the use of brute terror." Russian and world history scholar John M. Thompson places personal responsibility directly on Joseph Stalin. According to him, "much of what occurred only makes sense if it stemmed in part from the disturbed mentality, pathological cruelty, and extreme paranoia of Stalin himself. Insecure, despite having established a dictatorship over the party and country, hostile and defensive when confronted with criticism of the excesses of collectivization and the sacrifices required by high-tempo industrialization, and deeply suspicious that past, present, and even yet unknown future opponents were plotting against him, Stalin began to act as a person beleaguered. He soon struck back at enemies, real or imaginary." Professors Pablo Montagnes and Stephane Wolton posit that the purges in the Soviet Union and China can be attributed to the personalist leadership of Stalin and Mao, who were incentivized by having both control of the security apparatus used to carry out the purges and control of the appointment of replacements for those purged. Slovenian philosopher Slavoj Žižek attributes Mao allegedly viewing human life as disposable to his "cosmic perspective" on humanity.

Soviet Union
Adam Jones writes that "there is very little in the record of human experience to match the violence which was unleashed between 1917, when the Bolsheviks took power, and 1953, when Joseph Stalin died and the Soviet Union moved to adopt a more restrained and largely non-murderous domestic policy." Jones states that the exceptions to this were the Khmer Rouge (in relative terms) and Mao's rule in China (in absolute terms).

Stephen G. Wheatcroft says that prior to the opening of the Soviet archives for historical research, "our understanding of the scale and the nature of Soviet repression has been extremely poor" and that some scholars who wish to maintain pre-1991 high estimates are "finding it difficult to adapt to the new circumstances when the archives are open and when there are plenty of irrefutable data", and instead "hang on to their old Sovietological methods with round-about calculations based on odd statements from emigres and other informants who are supposed to have superior knowledge", although he acknowledged that even the figures estimated from the additional documents are not "final or definitive." In the 2007 revision of his book The Great Terror, Robert Conquest estimates that while exact numbers will never be certain, the communist leaders of the Soviet Union were responsible for no fewer than 15 million deaths.

Some historians attempt to make separate estimates for different periods of Soviet history, with casualty estimates varying widely. Timothy D. Snyder estimates 6 million for the Stalinist period. Alec Nove estimates 8.1 million for the period ending in 1937. Stéphane Courtois estimates 20 million and Alexander Yakovlev estimates 20-25 million for the entire period of Soviet rule. Rudolph Rummel estimates 61 million for the 1917–1987 period.

Red Terror
The Red Terror was a period of political repression and executions carried out by Bolsheviks after the beginning of the Russian Civil War in 1918. During this period, the political police (the Cheka) conducted summary executions of tens of thousands of "enemies of the people." Many victims were "bourgeois hostages" rounded up and held in readiness for summary execution in reprisal for any alleged counter-revolutionary provocation. Many were put to death during and after the suppression of revolts, such as the Kronstadt rebellion of Baltic Fleet sailors and the Tambov Rebellion of Russian peasants. Professor Donald Rayfield writes that "the repression that followed the rebellions in Kronstadt and Tambov alone resulted in tens of thousands of executions." A large number of Orthodox clergymen were also killed.

According to Nicolas Werth, the policy of decossackization amounted to an attempt by Soviet leaders to "eliminate, exterminate, and deport the population of a whole territory." In the early months of 1919, perhaps 10,000 to 12,000 Cossacks were executed and many more deported after their villages were razed to the ground. Historian Michael Kort wrote: "During 1919 and 1920, out of a population of approximately 1.5 million Don Cossacks, the Bolshevik regime killed or deported an estimated 300,000 to 500,000."

Joseph Stalin
Estimates of the number of deaths which were brought about by Stalin's rule are hotly debated by scholars in the fields of Soviet and Communist studies. Prior to the dissolution of the Soviet Union and the archival revelations which followed it, some historians estimated that the number of people who were killed by Stalin's regime was 20 million or higher. Michael Parenti writes that estimates on the Stalinist death toll vary widely in part because such estimates are based on anecdotes in absence of reliable evidence and "speculations by writers who never reveal how they arrive at such figures."

After the Soviet Union dissolved, evidence from the Soviet archives became available, containing official records of the execution of approximately 800,000 prisoners under Stalin for either political or criminal offenses, around 1.7 million deaths in the Gulags and some 390,000 deaths which occurred during kulak forced settlements in the Soviet Union, for a total of about 3 million officially recorded victims in these categories. According to Golfo Alexopoulos, Anne Applebaum, Oleg Khlevniuk, and Michael Ellman, official Soviet documentation of Gulag deaths is widely considered inadequate, as they write that the government frequently released prisoners on the edge of death in order to avoid officially counting them. A 1993 study of archival data by J. Arch Getty et al. showed that a total of 1,053,829 people died in the Gulag from 1934 to 1953. In 2010, Steven Rosefielde posited that this number has to be augmented by 19.4 percent in light of more complete archival evidence to 1,258,537, with the best estimate of Gulag deaths being 1.6 million from 1929 to 1953 when excess mortality is taken into account. Alexopolous estimates a much higher total of at least 6 million dying in the Gulag or shortly after release. Dan Healey has called her work a "challenge to the emergent scholarly consensus", while Jeffrey Hardy has criticized Alexopoulos for basing her assertions primarily on indirect and misinterpreted evidence.

According to historian Stephen G. Wheatcroft, Stalin's regime can be charged with causing the purposive deaths of about a million people. Wheatcroft excludes all famine deaths as purposive deaths and posits that those which qualify fit more closely the category of execution rather than murder. Others posit that some of the actions of Stalin's regime, not only those during the Holodomor but also dekulakization and targeted campaigns against particular ethnic groups, such as the Polish operation of the NKVD, can be considered as genocide at least in its loose definition. Modern data for the whole of Stalin's rule was summarized by Timothy Snyder, who stated that under the Stalinist regime there were six million direct deaths and nine million in total, including the deaths from deportation, hunger, and Gulag deaths. Ellman attributes roughly 3 million deaths to the Stalinist regime, excluding excess mortality from famine, disease, and war. Several popular press authors, among them Stalin biographer Simon Sebag Montefiore, Soviet/Russian historian Dmitri Volkogonov, and the director of Yale's "Annals of Communism" series Jonathan Brent, still put the death toll from Stalin at about 20 million.

Mass deportations of ethnic minorities
The Soviet government during Stalin's rule conducted a series of deportations on an enormous scale that significantly affected the ethnic map of the Soviet Union. Deportations took place under extremely harsh conditions, often in cattle carriages, with hundreds of thousands of deportees dying en route. Some experts estimate that the proportion of deaths from the deportations could be as high as one in three in certain cases. Raphael Lemkin, a lawyer of Polish-Jewish descent who initiated the Genocide Convention in 1948 and coined genocide, assumed that genocide was perpetrated in the context of the mass deportation of the Chechens, Ingush people, Volga Germans, Crimean Tatars, Kalmyks, and Karachays.

Regarding the fate of the Crimean Tatars, Amir Weiner of Stanford University writes that the policy could be classified as ethnic cleansing. In the book Century of Genocide, Lyman H. Legters writes: "We cannot properly speak of a completed genocide, only of a process that was genocidal in its potentiality." In contrast to this view, Jon K. Chang posits that the deportations had been in fact based on genocides based on ethnicity and that "social historians" in the West have failed to champion the rights of marginalized ethnicities in the Soviet Union. This view is supported by several countries. On 12 December 2015, the Ukrainian Parliament issued a resolution recognizing the 1944 deportation of Crimean Tatars (the Sürgünlik) as genocide and established the 18th of May as the Day of Remembrance for the victims of the Crimean Tatar Genocide. The Parliament of Latvia recognized the event as an act of genocide on 9 May 2019. The Parliament of Lithuania did the same on 6 June 2019. The Parliament of Canada passed a motion on 10 June 2019, recognizing the Crimean Tatar deportation as a genocide perpetrated by Soviet dictator Stalin, designating the 18th of May to be a day of remembrance. The deportation of Chechens and Ingush was acknowledged by the European Parliament as an act of genocide in 2004, stating: "Believes that the deportation of the entire Chechen people to Central Asia on 23 February 1944 on the orders of Stalin constitutes an act of genocide within the meaning of the Fourth Hague Convention of 1907 and the Convention for the Prevention and Repression of the Crime of Genocide adopted by the UN General Assembly on 9 December 1948."

Soviet famine of 1932–1933
Within the Soviet Union, forced changes in agricultural policies (collectivization), confiscations of grain and droughts caused the Soviet famine of 1932–1933 in the Ukrainian SSR (Holodomor), North Caucasus Krai, Volga region, and Kazakh SSR. The famine was most severe in Ukrainian, where it is often referenced as the Holodomor. A significant portion of the famine victims (3.3 to 7.5 million) were Ukrainians. Another part of the famine was that in Kazakhstan, also known as the Kazakh catastrophe, when more than 1.3 million ethnic Kazakhs (about 38% of the population) died.

While there is still a debate among scholars on whether the Holodomor was a genocide, some scholars say the Stalinist policies that caused the famine may have been designed as an attack on the rise of Ukrainian nationalism and may fall under the legal definition of genocide by the United Nations's Genocide Convention. The famine was officially recognized as genocide by the Ukraine and other governments. In a draft resolution, the Parliamentary Assembly of the Council of Europe declared that the famine was caused by the "cruel and deliberate actions and policies of the Soviet regime" and was responsible for the deaths of "millions of innocent people" in Ukraine, Belarus, Kazakhstan, Moldova, and Russia. Relative to its population, Kazakhstan is believed to have been the most adversely affected. Regarding the Kazakh famine, Michael Ellman states that it "seems to be an example of 'negligent genocide' which falls outside the scope of the UN Convention of genocide."

Great Purge
Stalin's attempts to solidify his position as leader of the Soviet Union led to an escalation of detentions and executions, climaxing in 1937–1938, a period sometimes referred to as the Yezhovshchina' after Cheka official Nikolay Yezhov, or Yezhov era, and continuing until Stalin's death in 1953. Around 700,000 of these were executed by a gunshot to the back of the head. Others perished from beatings and torture while in "investigative custody" and in the Gulag due to starvation, disease, exposure, and overwork.

Arrests were typically made citing Article 58 (RSFSR Penal Code) about counter-revolutionary laws, which included failure to report treasonous actions and in an amendment added in 1937 failing to fulfill one's appointed duties. In the cases investigated by the State Security Department of the NKVD from October 1936 to November 1938, at least 1,710,000 people were arrested and 724,000 people executed. Modern historical studies estimate a total number of repression deaths during 1937–1938 as 950,000–1,200,000. These figures take into account the incompleteness of official archival data and include both execution deaths and Gulag deaths during that period. Former kulaks and their families made up the majority of victims, with 669,929 people arrested and 376,202 executed.

The NKVD conducted a series of national operations which targeted some ethnic groups. A total of 350,000 were arrested and 247,157 were executed. Of these, the Polish operation of the NKVD, which targeted the members of Polska Organizacja Wojskowa, appears to have been the largest, with 140,000 arrests and 111,000 executions. Although these operations might well constitute genocide as defined by the United Nations convention, or "a mini-genocide" according to Simon Sebag Montefiore, there is as yet no authoritative ruling on the legal characterization of these events. Citing church documents, Alexander Nikolaevich Yakovlev has estimated that over 100,000 priests, monks, and nuns were executed during this time. Regarding the persecution of clergy, Michael Ellman has stated that "the 1937–38 terror against the clergy of the Russian Orthodox Church and of other religions (Binner & Junge 2004) might also qualify as genocide." In the summer and autumn of 1937, Stalin sent NKVD agents to the Mongolian People's Republic and engineered a Mongolian Great Terror in which some 22,000 or 35,000 people were executed. Around 18,000 victims were Buddhist lamas. In Belarus, mass graves for several thousand civilians killed by the NKVD between 1937 and 1941 were discovered in 1988 at Kurapaty.

Soviet killings during World War II
Following the Soviet invasion of Poland in September 1939, NKVD task forces started removing "Soviet-hostile elements" from the conquered territories. The NKVD systematically practiced torture which often resulted in death. According to the Polish Institute of National Remembrance, 150,000 Polish citizens perished due to Soviet repression during the war. The most notorious killings occurred in the spring of 1940, when the NKVD executed some 21,857 Polish POWs and intellectual leaders in what has become known as the Katyn massacre. Executions were also carried out after the annexation of the Baltic states. During the initial phases of Operation Barbarossa, the NKVD and attached units of the Red Army massacred prisoners and political opponents by the tens of thousands before fleeing from the advancing Axis powers forces. Memorial complexes have been built at NKVD execution sites at Katyn and Mednoye in Russia, as well as a "third killing field" at Piatykhatky, Ukraine.

People's Republic of China
The Chinese Communist Party came to power in China in 1949 after a long and bloody civil war between communists and the nationalist Kuomintang. There is a general consensus among historians that after Mao Zedong seized power, his policies and political purges directly or indirectly caused the deaths of tens of millions of people. Based on the Soviets' experience, Mao considered violence to be necessary in order to achieve an ideal society that would be derived from Marxism and as a result he planned and executed violence on a grand scale.

Campaign to Suppress Counterrevolutionaries
The first large-scale killings under Mao took place during his land reform and the campaign to suppress counter-revolutionaries. According to Daniel Goldhagen, official study materials published in 1948 show that Mao envisaged that "one-tenth of the peasants", or about 50,000,000, "would have to be destroyed" to facilitate agrarian reform. The exact number of people who were killed during Mao's land reform is believed to have been lower; according to Rudolph Rummel and Philip Short, at least one million people were killed. The suppression of counter-revolutionaries targeted mainly former Kuomintang officials and intellectuals who were suspected of disloyalty. According to Yang Kuisong, at least 712,000 people were executed and 1,290,000 were imprisoned in labor camps known as Laogai.

Great Leap Forward and the Great Chinese Famine
Benjamin Valentino posits that the Great Leap Forward was a cause of the Great Chinese Famine and the worst effects of the famine were steered towards the regime's enemies. Those who were labeled "black elements" (religious leaders, rightists, and rich peasants) in earlier campaigns died in the greatest numbers because they were given the lowest priority in the allocation of food. In Mao's Great Famine, historian Frank Dikötter writes that "coercion, terror, and systematic violence were the very foundation of the Great Leap Forward" and it "motivated one of the most deadly mass killings of human history." Dikötter estimates that at least 2.5 million people were summarily killed or tortured to death during this period. His research in local and provincial Chinese archives indicates the death toll was at least 45 million: "In most cases the party knew very well that it was starving its own people to death." In a secret meeting at Shanghai in 1959, Mao issued the order to procure one third of all grain from the countryside, saying: "When there is not enough to eat people starve to death. It is better to let half of the people die so that the other half can eat their fill." In light of additional evidence of Mao's culpability, Rummel added those killed by the Great Famine to his total for Mao's democide for a total of 77 million killed.

Tibet
According to Jean-Louis Margolin in The Black Book of Communism, the Chinese communists carried out a cultural genocide against the Tibetans. Margolin states that the killings were proportionally larger in Tibet than they were in China proper and "one can legitimately speak of genocidal massacres because of the numbers that were involved." According to the Dalai Lama and the Central Tibetan Administration, "Tibetans were not only shot, but they were also beaten to death, crucified, burned alive, drowned, mutilated, starved, strangled, hanged, boiled alive, buried alive, drawn and quartered, and beheaded." Adam Jones, a scholar who specializes in genocide, states that after the 1959 Tibetan uprising, the Chinese authorized struggle sessions against reactionaries, during which "communist cadres denounced, tortured, and frequently executed enemies of the people." These sessions resulted in 92,000 deaths out of a total population of about 6 million. These deaths, Jones stressed, may not only be seen as a genocide, but they may also be seen as an eliticide, meaning "targeting the better educated and leadership oriented elements among the Tibetan population." Patrick French, the former director of the Free Tibet Campaign in London, writes that the Free Tibet Campaign and other groups have claimed that a total of 1.2 million Tibetans were killed by the Chinese since 1950 but after examining archives in Dharamsala, he found "no evidence to support that figure." French states that a reliable alternative number is unlikely to be known but estimates that as many as half a million Tibetans died "as a 'direct result' of the policies of the People's Republic of China", using historian Warren Smith's estimate of 200,000 people who are missing from population statistics in the Tibet Autonomous Region and extending that rate to the borderland regions.

Cultural Revolution
Sinologists Roderick MacFarquhar and Michael Schoenhals estimate that between 750,000 and 1.5 million people were killed in the violence of the Cultural Revolution in rural China alone. Mao's Red Guards were given carte blanche to abuse and kill people who were perceived to be enemies of the revolution. Sociologist Yang Su has written that these mass killing were an outcome of "the paradox of state sponsorship and state failure"; according to Yang, mass killings were concentrated in rural areas in the months after the establishment of county revolutionary committees, with mass killing being more likely in communities with more local party members. Repression by the local organizations may have been in response to the rhetoric of violence promoted by the provincial capitals as a result of mass factionalism in those capitals, and the "peaks of mass killings coincided with two announcements from the party center in July 1968 banning factional armed battles and disbanding mass organizations"; Yang writes that Mao's government designated class enemies using an artificial and arbitrary standard to accomplish two political tasks: "mobilizing mass compliance and resolving elite conflict", while the elastic nature of the category allowed it to "take on a genocidal dimension under extraordinary circumstances." Political scientists Evgeny Finkel and Scott Straus write that Su estimates up to three million people were "murdered by their neighbors in collective killings and struggle rallies. This happened even though the central government had not issued any mass killing orders or policies."

In August 1966, over 100 teachers were murdered by their students in western Beijing.

Tiananmen Square
Jean-Louis Margolin states that under Deng Xiaoping, at least 1,000 people were killed in Beijing and hundreds of people were also executed in the countryside after his government crushed demonstrations in Tiananmen Square in 1989. According to Louisa Lim in 2014, a group of victims' relatives in China called the "Tiananmen Mothers" has confirmed the identities of more than 200 of those who were killed. Alex Bellamy writes that this "tragedy marks the last time in which an episode of mass killing in East Asia was terminated by the perpetrators themselves, judging that they had succeeded."

Cambodia
The Killing Fields are a number of sites in Cambodia where large numbers of people were killed and their bodies were buried by the Khmer Rouge regime during its rule of the country, which lasted from 1975 to 1979, after the end of the Cambodian Civil War. Sociologist Martin Shaw described the Cambodian genocide as "the purest genocide of the Cold War era." The results of a demographic study of the Cambodian genocide concluded that the nationwide death toll from 1975 to 1979 amounted to 1,671,000 to 1,871,000, or 21 to 24 percent of the total Cambodian population as it was estimated to number before the Khmer Rouge took power. According to Ben Kiernan, the number of deaths which were specifically caused by execution is still unknown because many victims died from starvation, disease and overwork. Researcher Craig Etcheson of the Documentation Center of Cambodia suggests that the death toll was between 2 and 2.5 million, with a "most likely" figure of 2.2 million. After spending five years researching about 20,000 grave sites, he posited that "these mass graves contain the remains of 1,112,829 victims of execution." A study by French demographer Marek Sliwinski calculated slightly fewer than 2 million unnatural deaths under the Khmer Rouge out of a 1975 Cambodian population of 7.8 million, with 33.5% of Cambodian men dying under the Khmer Rouge compared to 15.7% of Cambodian women. The number of suspected victims of execution who were found in 23,745 mass graves is estimated to be 1.3 million according to a 2009 academic source. Execution is believed to account for roughly 60% of the total death toll during the genocide, with other victims succumbing to starvation or disease.

Helen Fein, a genocide scholar, states that the xenophobic ideology of the Khmer Rouge regime bears a stronger resemblance to "an almost forgotten phenomenon of national socialism", or fascism, rather than communism. Responding to Ben Kiernan's "argument that Pol Pot's Democratic Kampuchea regime was more racist and generically totalitarian than Marxist or specifically Communist", Steve Heder states that the example of such racialist thought as it is applied in relation to the minority Cham people echoed "Marx's definition of a historyless people doomed to extinction in the name of progress" and it was therefore a part of general concepts of class and class struggle. Craig Etcheson writes that data on the distribution and origin of the mass graves as well as internal Khmer Rouge security documents, leads to the conclusion that "most of the violence was carried out pursuant to orders from the highest political authorities of the Communist Party of Kampuchea", rather than being the result of the "spontaneous excesses of a vengeful, undisciplined peasant army", while French historian Henri Locard writes that the fascist label was applied to the Khmer Rouge by the Communist Party of Vietnam as a form of revisionism, but the repression which existed under the rule of the Khmer Rouge was "similar (if significantly more lethal) to the repression in all communist regimes." Daniel Goldhagen states that the Khmer Rouge were xenophobic because they believed that the Khmer people were "the one authentic people capable of building true communism." Steven Rosefielde writes that Democratic Kampuchea was the deadliest of all communist regimes on a per capita basis, primarily because it "lacked a viable productive core" and it "failed to set boundaries on mass murder."

Other states
Barbara Harff and Ted Gurr write: "Most Marxist–Leninist regimes which came to power through protracted armed struggle in the postwar period perpetrated one or more politicides, though of vastly different magnitudes." According to Benjamin Valentino, most regimes that described themselves as communist did not commit mass killings, but in communist states such as Bulgaria, Romania, and East Germany, mass killings were committed on a scale which was smaller than his standard of 50,000 people who were killed within a period of five years, although the lack of documentation prevents a definitive judgement about the scale of these events and the motives of their perpetrators. Atsushi Tago and Frank Wayman write that because democide is broader than mass killing or genocide, most communist regimes can be said to have engaged in it, including the Soviet Union, China, Cambodia, North Vietnam, East Germany, Poland, Czechoslovakia, Hungary, North Korea, Cuba, Laos, Albania, and Yugoslavia.

People's Republic of Bulgaria
According to Valentino, between 50,000 and 100,000 people may have been killed in Bulgaria beginning in 1944 as part of a campaign of agricultural collectivization and political repression, although there is insufficient documentation to make a definitive judgement. In his book History of Communism in Bulgaria, Dinyu Sharlanov accounts for about 31,000 people who were killed by the regime between 1944 and 1989.

East Germany
According to Valentino, between 80,000 and 100,000 people may have been killed in East Germany beginning in 1945 as part of the Soviet denazification campaign; other scholars posit that these estimates are inflated.

Immediately after World War II, denazification commenced in Allied-occupied Germany and regions the Nazis had annexed. In the Soviet occupation zone of Germany, the NKVD established prison camps, usually in abandoned Nazi concentration camps, and they used them to intern alleged Nazis and Nazi German officials, along with some landlords and Prussian Junkers. According to files and data released by the Soviet Ministry for the Interior in 1990, 123,000 Germans and 35,000 citizens of other nations were detained. Of these prisoners, a total of 786 people were shot and 43,035 people died of various causes. Most of the deaths were not direct killings but were caused by outbreaks of dysentery and tuberculosis. Deaths from starvation also occurred on a large scale, particularly from late 1946 to early 1947, but these deaths do not appear to have been deliberate killings because food shortages were widespread in the Soviet occupation zone. The prisoners in the "silence camps", as the NKVD special camps were called, did not have access to the black market and were only able to get food that was handed to them by the authorities. Some prisoners were executed and others may have been tortured to death. In this context, it is difficult to determine if the prisoner deaths in the silence camps can be categorized as mass killings. It is also difficult to determine how many of the dead were Germans, East Germans, or members of other nationalities.

East Germany's government erected the Berlin Wall following the Berlin Crisis of 1961. Even though crossing between East Germany and West Germany was possible for motivated and approved travelers, thousands of East Germans tried to defect by illegally crossing the wall. Of these, between 136 and 227 people were killed by the Berlin Wall's guards during the years of the wall's existence (1961-1989).

Socialist Republic of Romania
Investigations conducted by the Association of Former Political Prisoners of Romania in Constanța, based on death records from the villages found along the Canal route, indicate 6,355 "Canal workers" (a euphemism for detainees) died during the 1949–1953 period of forced labor in the construction of the Danube-Black Sea Canal, while political analyst Vladimir Socor estimates the number of deaths to be "considerably in excess of 10,000". An additional 1,700 died due to the Bărăgan deportations of the 1950s. Due to radical pro-natalism, many children were sent to government run orphanages in Romania where 20,000 children may have died. Higher estimates have been made of the total victims of the regime. According to Valentino, between 60,000 and 300,000 people may have been killed in Romania beginning in 1945 as part of agricultural collectivization and political repression.

Socialist Federal Republic of Yugoslavia
The communist regime of Josip Broz Tito bloodily repressed opponents and committed several massacres of prisoners of war after the World War II. The European Public Hearing on Crimes Committed by Totalitarian Regimes reports: "The decision to 'annihilate' opponents must had been adopted in the closest circles of the Yugoslav state leadership, and the order was certainly issued by the Supreme Commander of the Yugoslav Army Josip Broz Tito, although it is not known when or in what form."

Dominic McGoldrick writes that as the head of a "highly centralised and oppressive" dictatorship, Tito wielded tremendous power in Yugoslavia, with his dictatorial rule administered through an elaborate bureaucracy which routinely suppressed human rights. Eliott Behar states that "Tito's Yugoslavia was a tightly controlled police state", and outside the Soviet Union, Yugoslavia had more political prisoners than all of the rest of Eastern Europe combined, according to David Mates. Tito's secret police was modelled on the Soviet KGB. Its members were ever-present and they often acted extrajudicially, with victims including middle-class intellectuals, liberals, and democrats. Yugoslavia was a signatory to the International Covenant on Civil and Political Rights but scant regard was paid to some of its provisions.

North Korea
According to Rudolph Rummel, forced labor, executions, and concentration camps were responsible for over one million deaths in the Democratic People's Republic of Korea (DPRK) from 1948 to 1987. Others have estimated that 400,000 people died in North Korea's concentration camps alone. A wide range of atrocities have been committed in the camps including forced abortions, infanticide and torture. Former International Criminal Court judge Thomas Buergenthal, who was one of the Report of the Commission of Inquiry on Human Rights in the Democratic People's Republic of Korea's authors and a child survivor of Auschwitz, told The Washington Post that "conditions in the [North] Korean prison camps are as terrible, or even worse, than those I saw and experienced in my youth in these Nazi camps and in my long professional career in the human rights field." Pierre Rigoulot estimates 100,000 executions, 1.5 million deaths through concentration camps and slave labor, and 500,000 deaths from famine. During the Korean War, the DPRK "liquidated" 29,000 civilians during the North Korean occupation of South Korea, June to September, 1950.

The famine, which claimed as many as one million lives, has been described as the result of the economic policies pursued by the North Korean government and deliberate "terror-starvation"; in 2010, Steven Rosefielde stated that the Red Holocaust "still persists in North Korea", as Kim Jong Il "refuses to abandon mass killing." Adam Jones cites journalist Jasper Becker's claim that the famine was a form of mass killing or genocide due to political manipulations of food. Estimates based on a North Korean 2008 census suggest 240,000 to 420,000 excess deaths as a result of the 1990s North Korean famine and a demographic impact of 600,000 to 850,000 fewer people in North Korea in 2008 as a result of poor living conditions after the famine.

Democratic Republic of Vietnam
Valentino attributes 80,000–200,000 deaths to "communist mass killings" in North and South Vietnam.

According to scholarship based on Vietnamese and Hungarian archival evidence, as many as 15,000 suspected landlords were executed during North Vietnam's land reform from 1953 to 1956. The North Vietnamese leadership planned in advance to execute 0.1% of North Vietnam's population (estimated at 13.5 million in 1955) as "reactionary or evil landlords", although this ratio could vary in practice. Dramatic errors were committed in the course of the land reform campaign. Vu Tuong states that the number of executions during North Vietnam's land reform was proportionally comparable to executions during Chinese land reform from 1949 to 1952.

Cuba
According to Jay Ulfelder and Benjamin Valentino, the Fidel Castro government of Cuba killed between 5,000 and 8,335 noncombatants as a part of the campaign of political repression between 1959 and 1970.

Democratic Republic of Afghanistan
According to Frank Wayman and Atsushi Tago, although frequently considered an example of communist genocide, the Democratic Republic of Afghanistan represents a borderline case. Prior to the Soviet–Afghan War, the People's Democratic Party of Afghanistan executed between 10,000 and 27,000 people, mostly at Pul-e-Charkhi prison. Mass graves of executed prisoners have been exhumed dating back to the Soviet era.

After the invasion in 1979, the Soviets installed the puppet government of Babrak Karmal. By 1987, about 80% of the country's territory was permanently controlled by neither the pro-communist government and supporting Soviet troops nor by the armed opposition. To tip the balance, the Soviet Union used a tactic that was a combination of scorched earth policy and migratory genocide. By systematically burning the crops and destroying villages in rebel provinces as well as by reprisal bombing entire villages suspected of harboring or supporting the resistance, the Soviets tried to force the local population to move to Soviet controlled territory, thereby depriving the armed opposition of support. Valentino attributes between 950,000 and 1,280,000 civilian deaths to the Soviet invasion and occupation of the country between 1978 and 1989, primarily as counter-guerrilla mass killing. By the early 1990s, approximately one-third of Afghanistan's population had fled the country. M. Hassan Kakar said that "the Afghans are among the latest victims of genocide by a superpower."

People's Democratic Republic of Ethiopia
Amnesty International estimates that half a million people were killed during the Ethiopian Red Terror of 1977 and 1978. During the terror, groups of people were herded into churches that were then burned down and women were subjected to systematic rape by soldiers. The Save the Children Fund reported that victims of the Red Terror included not only adults, but 1,000 or more children, mostly aged between eleven and thirteen, whose corpses were left in the streets of Addis Ababa. Ethiopian dictator Mengistu Haile Mariam himself is alleged to have killed political opponents with his bare hands.

Debate over famines
According to historian J. Arch Getty, over half of the 100 million deaths which are attributed to communism were due to famines. Stéphane Courtois posits that many communist regimes caused famines in their efforts to forcibly collectivize agriculture and systematically used it as a weapon by controlling the food supply and distributing food on a political basis. Courtois states that "in the period after 1918, only Communist countries experienced such famines, which led to the deaths of hundreds of thousands, and in some cases millions, of people. And again in the 1980s, two African countries that claimed to be Marxist–Leninist, Ethiopia and Mozambique, were the only such countries to suffer these deadly famines."

Scholars Stephen G. Wheatcroft, R. W. Davies, and Mark Tauger reject the idea that the Ukrainian famine was an act of genocide that was intentionally inflicted by the Soviet government. Getty posits that the "overwhelming weight of opinion among scholars working in the new archives is that the terrible famine of the 1930s was the result of Stalinist bungling and rigidity rather than some genocidal plan." Novelist Aleksandr Solzhenitsyn opined in a 2 April 2008 article in Izvestia that the 1930s famine in the Ukraine was no different from the Russian famine of 1921–1922, as both were caused by the ruthless robbery of peasants by Bolshevik grain procurements.

Pankaj Mishra questions Mao's direct responsibility for famine, stating: "A great many premature deaths also occurred in newly independent nations not ruled by erratic tyrants." Mishra cites Nobel laureate Amartya Sen's research demonstrating that democratic India suffered more excess mortality from starvation and disease in the second half of the 20th century than China did. Sen wrote: "India seems to manage to fill its cupboard with more skeletons every eight years than China put there in its years of shame."

Benjamin Valentino writes: "Although not all the deaths due to famine in these cases were intentional, communist leaders directed the worst effects of famine against their suspected enemies and used hunger as a weapon to force millions of people to conform to the directives of the state." Daniel Goldhagen says that in some cases deaths from famine should not be distinguished from mass murder, commenting: "Whenever governments have not alleviated famine conditions, political leaders decided not to say no to mass death – in other words, they said yes." Goldhagen says that instances of this occurred in the Mau Mau Rebellion, the Great Leap Forward, the Nigerian Civil War, the Eritrean War of Independence, and the War in Darfur. Martin Shaw posits that if a leader knew the ultimate result of their policies would be mass death by famine, and they continue to enact them anyway these death can be understood as intentional.

Historian and journalists, such as Seumas Milne and Jon Wiener, have criticized the emphasis on communism when assigning blame for famines. In a 2002 article for The Guardian, Milne mentions "the moral blindness displayed towards the record of colonialism", and he writes: "If Lenin and Stalin are regarded as having killed those who died of hunger in the famines of the 1920s and 1930s, then Churchill is certainly responsible for the 4 million deaths in the avoidable Bengal famine of 1943." Milne laments that while "there is a much-lauded Black Book of Communism, [there exists] no such comprehensive indictment of the colonial record." Weiner makes a similar assertion while comparing the Holodomor and the Bengal famine of 1943, stating that Winston Churchill's role in the Bengal famine "seems similar to Stalin's role in the Ukrainian famine." Historian Mike Davis, author of Late Victorian Holocausts, draws comparisons between the Great Chinese Famine and the Indian famines of the late 19th century, arguing that in both instances the governments which oversaw the response to the famines deliberately chose not to alleviate conditions and as such bear responsibility for the scale of deaths in said famines.

Historian Michael Ellman is critical of the fixation on a "uniquely Stalinist evil" when it comes to excess deaths from famines. Ellman posits that mass deaths from famines are not a "uniquely Stalinist evil", commenting that throughout Russian history, famines, and droughts have been a common occurrence, including the Russian famine of 1921–1922, which occurred before Stalin came to power. He also states that famines were widespread throughout the world in the 19th and 20th centuries in countries such as India, Ireland, Russia and China. According to Ellman, the G8 "are guilty of mass manslaughter or mass deaths from criminal negligence because of their not taking obvious measures to reduce mass deaths" and Stalin's "behaviour was no worse than that of many rulers in the nineteenth and twentieth centuries."

Legal status and prosecutions
According to a 1992 constitutional amendment in the Czech Republic, a person who publicly denies, puts in doubt, approves, or tries to justify Nazi or communist genocide or other crimes of Nazis or communists will be punished with a prison term of 6 months to 3 years. In 1992, Barbara Harff wrote that no communist country or governing body has ever been convicted of genocide. In his 1999 foreword to The Black Book of Communism, Martin Malia wrote: "Throughout the former Communist world, moreover, virtually none of its responsible officials has been put on trial or punished. Indeed, everywhere Communist parties, though usually under new names, compete in politics."

At the conclusion of a trial lasting from 1994 to 2006, Ethiopia's former ruler Mengistu Haile Mariam was convicted of genocide, war crimes, and crimes against humanity, and sentenced to death by an Ethiopian court for his role in Ethiopia's Red Terror. Ethiopian law is distinct from the United Nations' Genocide Convention and other definitions in that it defines genocide as intent to wipe out political and not just ethnic groups. In this respect, it closely resembles the definition of politicide.

In 1997, the Cambodian government asked the United Nations for assistance in setting up the Khmer Rouge Tribunal. The prosecution presented the names of five possible suspects to the investigating judges on 18 July 2007. On 26 July 2010, Kang Kek Iew (Comrade Duch), director of the S-21 prison camp in Democratic Kampuchea where more than 14,000 people were tortured and then murdered (mostly at nearby Choeung Ek), was convicted of crimes against humanity and sentenced to 35 years. His sentence was reduced to 19 years in part because he had been behind bars for 11 years. Nuon Chea, second in command of the Khmer Rouge and its most senior surviving member, was charged of war crimes and crimes against humanity but not of genocide. On 7 August 2014, he was convicted of crimes against humanity by the Khmer Rouge Tribunal and received a life sentence. Khieu Samphan, the Khmer Rouge head of state, was also convicted of crimes against humanity. In 2018, Nuon Chea and Khieu Samphan were convicted of genocide for "the attempted extermination of the Cham and Vietnamese minorities."

After restoration of their independence in 1991, the Baltic states started investigating crimes against humanity committed during the Soviet occupation, with most criminal cases focusing on deportation of civilians and extrajudicial killing of forest brethren. In 2013 Rain Liivoja estimated that Estonia had convicted eleven, Latvia nine, and Lithuania about dozen persons. Some former Soviet officials like Alfons Noviks, the former People’s Commissar of the Interior of the Latvian SSR, were explicitly convicted for genocide.

On 26 November 2010, the Russian State Duma issued a declaration acknowledging Stalin's responsibility for the Katyn massacre, the execution of over 21,000 Polish POW's and intellectual leaders by Stalin's NKVD. The declaration stated that archival material "not only unveils the scale of his horrific tragedy but also provides evidence that the Katyn crime was committed on direct orders from Stalin and other Soviet leaders."

Memorials and museums
Monuments to the victims of communism exist in almost all the capitals of Eastern Europe and there are also several museums which document the crimes which occurred during communist rule such as the Museum of Occupations and Freedom Fights in Lithuania, the Museum of the Occupation of Latvia in Riga and the House of Terror in Budapest, all three of these museums also document the crimes which occurred during Nazi rule. Several scholars, among them Kristen Ghodsee and Laure Neumayer, posit that these efforts seek to institutionalize the "victims of communism" narrative as a double genocide theory, or the moral equivalence between the Nazi Holocaust (race murder) and those killed by communist states (class murder), and that works such as The Black Book of Communism played a major role in the criminalization of communism in the European political space in the post Cold War-era. Zoltan Dujisin writes that "the Europeanization of an antitotalitarian 'collective memory' of communism reveals the emergence of a field of anticommunism" and the narrative is proposed by "anticommunist memory entrepreneurs."

In Washington D.C., a bronze statue modeled after the Goddess of Democracy sculpture, which was created during the 1989 Tiananmen Square protests, was dedicated as the Victims of Communism Memorial in 2007, having been authorized by the Congress in 1993. The Victims of Communism Memorial Foundation plans to build an International Museum on Communism in Washington. In 2002, the Memorial to the Victims of Communism was unveiled in Prague. In Hungary, the Gloria Victis Memorial to honor "the 100 million victims of communism" was erected in 2006 on the 50th anniversary of the Hungarian Revolution. As of 2008, Russia contained 627 memorials and memorial plaques which are dedicated to the victims of the communist terror, most of them were created by private citizens, but it did not have either a national monument or a national museum. The Wall of Grief in Moscow, inaugurated in October 2017, is Russia's first monument to the victims of political persecution by Stalin during the country's Soviet era. In 2017, Canada's National Capital Commission approved the design of the Memorial to the Victims of Communism – Canada, a Land of Refuge which will be built on the Garden of the Provinces and Territories in Ottawa. On 23 August 2018, Estonia's Victims of Communism 1940–1991 Memorial was inaugurated in Tallinn by Estonian president Kersti Kaljulaid. The memorial's construction was financed by the state and the memorial itself is being managed by the Estonian Institute of Historical Memory. The date of the opening ceremony was chosen because it coincided with the official European Day of Remembrance for the Victims of Stalinism and Nazism.

Controversies
The concept of mass killing as a phenomenon unique to communist governments, or ideologically inherent within them, is heavily disputed.

Many commentators on the political right state that the mass killings under communist regimes are an indictment of communism. Opponents of this hypothesis state that these killings were aberrations caused by specific authoritarian regimes, and not caused by communism itself, and point to mass deaths in wars that they claim were caused by capitalism and anti-communism as a counterpoint to those killings.