The Cambodian genocide was the systematic persecution and killing of Cambodian citizens by the Khmer Rouge under the general secretaryship of Pol Pot. It resulted in the deaths of approximately 2 million people from 1975 to 1979, around 25% of Cambodia's population in 1975 (c. 7.8 million).
For many years, Pol Pot and the Khmer Rouge were supported by the Chinese Communist Party (CCP), led by Mao Zedong; it is estimated that at least 90% of the foreign aid which the Khmer Rouge received came from China, including at least US $1 billion in interest-free economic and military aid in 1975 alone. After it seized power in April 1975, the Khmer Rouge wanted to turn the country into an agrarian socialist republic, founded on the policies of ultra-Maoism and influenced by the Cultural Revolution. Pol Pot and other Khmer Rouge officials met with Mao in Beijing in June 1975, receiving approval and advice, while high-ranking CCP officials such as Politburo Standing Committee member Zhang Chunqiao later visited Cambodia to offer help. To fulfill its goals, the Khmer Rouge emptied the cities and marched Cambodians to labor camps in the countryside, where mass executions, forced labor, physical abuse, torture, starvation, and disease were rampant. In 1976, the Khmer Rouge renamed the country Democratic Kampuchea.
The massacres ended when the Vietnamese military invaded in 1978 and toppled the Khmer Rouge regime. By January 1979, 1.5 to 2 million people, amounting to 20% to 25% of the country's 1975 population, had died due to the Khmer Rouge's policies, including 200,000–300,000 Chinese Cambodians, 90,000–500,000 Cambodian Cham (who are mostly Muslim), and 20,000 Vietnamese Cambodians. 20,000 people passed through the Security Prison 21, one of the 196 prisons the Khmer Rouge operated, and only seven adults survived. The prisoners were taken to the Killing Fields, where they were executed (often with pickaxes, to save bullets) and buried in mass graves. Abduction and indoctrination of children was widespread, and many were persuaded or forced to commit atrocities. As of 2009, the Documentation Center of Cambodia has mapped 23,745 mass graves containing approximately 1.3 million suspected victims of execution. Direct execution is believed to account for up to 60% of the genocide's death toll, with other victims succumbing to starvation, exhaustion, or disease.
The genocide triggered a second outflow of refugees, many of whom escaped to neighboring Thailand and, to a lesser extent, Vietnam. In 2003, by agreement between the Cambodian government and the United Nations, the Extraordinary Chambers in the Court of Cambodia (Khmer Rouge Tribunal) were established to try the members of the Khmer Rouge leadership responsible for the Cambodian genocide. Trials began in 2009. On 26 July 2010, the Trial Chamber convicted Kang Kek Iew for crimes against humanity and grave breaches of the 1949 Geneva Conventions. The Supreme Court Chamber increased his sentence to life imprisonment. Nuon Chea and Khieu Samphan were tried and convicted in 2014 of crimes against humanity and grave breaches of the Geneva Conventions. On 28 March 2019, the Trial Chamber found Nuon Chea and Khieu Samphan guilty of crimes against humanity, grave breaches of the Geneva Conventions, and genocide of the Vietnamese ethnic, national and racial group. The Chamber additionally convicted Nuon Chea of genocide of the Cham ethnic and religious group under the doctrine of superior responsibility. Both Nuon Chea and Khieu Samphan were sentenced to terms of life imprisonment.
Historical background
Rise of the Khmer Rouge
Cambodian Civil War
In 1968, the Khmer Rouge officially launched a nationwide insurgency across Cambodia. Though the government of North Vietnam was not informed about the Khmer Rouge's decision in advance, its forces still provided shelter and weapons. This support made it difficult for the Cambodian military to effectively counter the insurgents, and for the next two years, King Norodom Sihanouk did very little to stop it. The insurgency thus grew in strength, resulting in the party openly declaring itself the Communist Party of Kampuchea.
Sihanouk was deposed in 1970 by Premier Lon Nol, with the support of the National Assembly, establishing the pro-United States Khmer Republic. On the Chinese Communist Party (CCP)'s advice, Sihanouk, who was in exile in Beijing, formed an alliance with the Khmer Rouge, and became the nominal head of a Khmer Rouge–dominated government-in-exile (known by its French acronym, GRUNK) backed by China. Although thoroughly aware of the weakness of Lon Nol's forces and loath to commit American military force to the new conflict in any form other than air power, the Nixon administration announced its support for the new Khmer Republic.
On 29 March 1970, North Vietnam launched an offensive against the Cambodian army. Documents from the Soviet Union's archives reveal that the invasion was launched at the Khmer Rouge's explicit request after negotiations were held with Nuon Chea. A North Vietnamese force quickly overran large parts of eastern Cambodia, coming within 15 miles (24 km) of Phnom Penh before being pushed back. By June, three months after Sihanouk's removal, it had swept government forces from the entire northeastern third of the country. After defeating those forces, the Vietnamese turned the newly won territories over to the local insurgents. The Khmer Rouge also established "liberated" areas in the southern and southwestern parts of the country, where they operated independently of the Vietnamese.
After Sihanouk demonstrated his support for the Khmer Rouge by visiting them in the field, their ranks swelled from 6,000 to 50,000 fighters. Many of the new recruits were apolitical peasants who fought in support of the King, rather than for communism, of which they had little understanding.
By 1975, with Lon Nol's government running out of ammunition due to its loss of U.S. support, it was clear that its collapse was imminent. On 17 April 1975, the Khmer Rouge captured Phnom Penh and ended the civil war. Mortality estimates for the Cambodian Civil War vary widely. Sihanouk used a figure of 600,000 civil war deaths, while Elizabeth Becker reported over a million civil war deaths, military and civilian included. Other researchers were unable to corroborate such high estimates. Marek Sliwinski notes that many estimates of the dead are open to question and may have been used for propaganda, suggesting that the true number lies between 240,000 and 310,000. Judith Banister and E. Paige Johnson described 275,000 war deaths as "the highest mortality that we can justify". Patrick Heuveline states that "Subsequent reevaluations of the demographic data situated the death toll for the [civil war] in the order of 300,000 or less".
United States bombing campaign
From 1970 to 1973, a massive United States bombing campaign against the Khmer Rouge devastated rural Cambodia. An earlier U.S. bombing campaign of Cambodia began on 18 March 1969 with Operation Menu, but U.S. bombing in Cambodia had commenced years before that.
The number of Cambodian civilian and Khmer Rouge deaths caused by U.S. bombing is disputed and difficult to disentangle from the broader Cambodian Civil War. Estimates range from 30,000 to 500,000. Sliwinski estimates that 17% of total civil war deaths can be attributed to U.S. bombing, noting that this is far behind the leading causes of death, as the U.S. bombing was concentrated in underpopulated border areas. Ben Kiernan attributes 50,000 to 150,000 deaths to the U.S. bombing.
The relationship between the United States' massive bombing of Cambodia and the growth of the Khmer Rouge in recruitment and popular support has been a matter of interest to historians. Some scholars, including Michael Ignatieff, Adam Jones, and Greg Grandin, have cited the United States intervention and bombing campaign from 1965 to 1973 as a significant factor in increasing the Cambodian peasantry's support for the Khmer Rouge. According to Ben Kiernan, the Khmer Rouge "would not have won power without U.S. economic and military destabilization of Cambodia. ... It used the bombing's devastation and massacre of civilians as recruitment propaganda and as an excuse for its brutal, radical policies and its purge of moderate communists and Sihanoukists."
Pol Pot biographer David P. Chandler writes that the bombing "had the effect the Americans wanted—it broke the Communist encirclement of Phnom Penh", but also accelerated the collapse of rural society and increased social polarization. Craig Etcheson agrees that U.S. intervention increased recruitment for the Khmer Rouge but disputes that it was a primary cause of the Khmer Rouge victory. According to William Shawcross, the United States bombing and ground incursion plunged Cambodia into the chaos that Sihanouk had worked to prevent the outbreak of for years.
International supporters of the Khmer Rouge
China
Since the 1950s, Pol Pot (General Secretary of the Communist Party of Kampuchea from 1963 to 1981) had made frequent visits to the People's Republic of China, where he received political and military training—especially on the theory of the dictatorship of the proletariat—from the personnel of the CCP. From November 1965 to February 1966, high-ranking CCP officials such as Chen Boda and Zhang Chunqiao trained him on topics such as the communist revolution in China, class conflicts, Communist International, etc. Pol Pot also met with other officials, including Deng Xiaoping and Peng Zhen. He was particularly impressed by Kang Sheng's lecture on how to conduct a political purge.
In 1970, Lon Nol overthrew Sihanouk, who fled to Beijing, where Pol Pot was also visiting. On the CCP's advice, the Khmer Rouge changed its position, and to support Sihanouk, it established the National United Front of Kampuchea. In 1970 alone, the Chinese reportedly gave the United Front 400 tons of military aid. In April 1974, Sihanouk and Khmer Rouge leaders Ieng Sary and Khieu Samphan met with Mao in Beijing; Mao supported many of the policies the Khmer Rouge proposed but did not want it to marginalize Sihanouk after it won the civil war and established a new Cambodia.
In June 1975, Pol Pot and other Khmer Rouge officials met with Mao in Beijing, where Mao lectured Pol Pot on his "Theory of Continuing Revolution under the Dictatorship of the Proletariat (无产阶级专政下继续革命理论)", recommending two articles by Yao Wenyuan and sending Pol Pot over 30 books by Karl Marx, Friedrich Engels, Vladimir Lenin, and Joseph Stalin. During this meeting, Mao told Pol Pot:
We agree with you! Much of your experience is better than ours. China is not qualified to criticize you. We committed errors of the political routes for ten times in fifty years—some are national, some are local…Thus I say China has no qualification to criticize you but to applaud you. You are basically correct…During the transition from the democratic revolution to adopting a socialist path, there exist two possibilities: one is socialism, the other is capitalism. Our situation now is like this. Fifty years from now, or one hundred years from now, the struggle between two lines will exist. Even ten thousand years from now, the struggle between two lines will still exist. When Communism is realized, the struggle between two lines will still be there. Otherwise, you are not a Marxist. This is unity existing among opposites. If one mentions only one side of the two, this is metaphysics. I believe in what Marx and Lenin have said, that the path [of advance] would be tortuous ... Our state now is, as Lenin said, a capitalist state without capitalists. This state protects capitalist rights, and the wages are not equal. Under the slogan of equality, a system of inequality has been introduced. There will exist a struggle between two lines, the struggle between the advanced and the backward, even when Communism is realized. Today we cannot explain it completely.
Pol Pot replied: "The issue of lines of struggle raised by Chairman Mao is an important strategic issue. We will follow your words in the future. I have read and learned various works of Chairman Mao since I was young, especially the theory on people's war. Your works have guided our entire party." On the other hand, during an August 1975 meeting, Chinese Premier Zhou Enlai warned Sihanouk as well as Khmer Rouge leaders including Khieu Samphan and Ieng Sary of the danger of radical movement toward communism, citing the mistakes in China's Great Leap Forward. Zhou urged them not to repeat the mistakes that had caused havoc. Sihanouk later recalled that Khieu Samphan and Ieng Thirith responded only with "an incredulous and superior smile".
During the genocide, China was the Khmer Rouge's largest military and economic supporter, supplying "more than 15,000 military advisers" and most of its external aid. It is estimated that at least 90% of foreign aid to Khmer Rouge came from China, with 1975 alone seeing US$1 billion in interest-free economic and military aid, "the biggest aid ever given to any one country by China". A series of internal crises in 1976 prevented Beijing from exerting substantial influence over Khmer Rouge policies.
Transition period
After Mao's death in September 1976, China underwent a two-year transitionary period that ended with the appointment of Deng Xiaoping as its new paramount leader in December 1978. During the transition period, Pol Pot made an official visit to China in July 1977 and was welcomed by CCP chairman Hua Guofeng and other high-ranking CCP officials, with the People's Daily calling him the "Comrade from Cambodia" (柬埔寨战友). Pol Pot also toured the agricultural production model of Dazhai, a product of Mao's era. Chen Yonggui, Vice Premier of China and the leader of Dazhai, visited Cambodia in December 1977, commending the achievement of its movement toward communism.
In 1978, Son Sen, a Khmer Rouge leader and the Minister of National Defense of Democratic Kampuchea, visited China and obtained its approval for military aid. In the same year, high-ranking CCP officials such as Wang Dongxing and Deng Yingchao visited Cambodia to offer support.
Deng era
Soon after Deng became the paramount leader of China, the Vietnamese invaded Cambodia and ended the genocide by defeating the Khmer Rouge in January 1979. The People's Republic of Kampuchea was then established. To counter the power of the Soviet Union and Vietnam in Southeast Asia, China officially condemned the Vietnamese invasion and continued its material support of the Khmer Rouge. In early 1979, China launched an invasion of Vietnam to retaliate against Vietnam's invasion of Cambodia. Deng informed U.S. President Jimmy Carter about the attack on Vietnam beforehand, during his visit to the United States soon after the People's Republic of China and the United States established formal diplomatic relations on January 1, 1979. Carter attempted to dissuade Deng from pursuing the military action, but did not succeed.
Deng was convinced by a conversation with Singapore's prime minister Lee Kuan Yew to limit the scale and duration of the war. After the one-month war, Singapore attempted to serve as a mediator between Vietnam and China on the Cambodian issue.