[10][11][12] 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.

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.

Documents which were uncovered 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.

Some scholars, including Michael Ignatieff, Adam Jones[55] and Greg Grandin,[56] have cited the United States intervention and bombing campaign from 1965 to 1973 as a significant factor that led to increased support for the Khmer Rouge among the Cambodian peasantry.

"[58] 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.

[62] Since the 1950s, Pol Pot (leader of the Khmer Rouge from 1963 to 1979) 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.

"[64] On the other hand, during another meeting in August 1975, Chinese Premier Zhou Enlai warned Sihanouk as well as Khmer Rouge leaders including Khieu Samphan and Ieng Sary of the danger of radical movement towards communism, citing the mistakes in China's own Great Leap Forward.

[74] 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 order to counter the power of the Soviet Union and Vietnam in Southeast Asia, China officially condemned the Vietnamese invasion and continued its material support to the Khmer Rouge.

[86] After the 1991 Paris Peace Accords, Thailand continued to allow the Khmer Rouge "to trade and move across the Thai border to sustain their activities ... although international criticism, particularly from the United States and Australia ... caused it to disavow passing any direct military support.

[89][better source needed] Attempts to implement these goals (formed upon the observations of small, rural communes) into a larger society were key factors in the ensuing genocide.

"[99] Quinn has written of the Khmer Rouge that "[w]hat emerges as the explanation for the terror and violence that swept Cambodia during the 1970s is that a small group of alienated intellectuals, enraged by their perception of a corrupt society and imbued with a Maoist plan to create a pure socialist order in the shortest possible time, recruited extremely young, poor, and envious cadres, instructed them in harsh and brutal methods learned from Stalinist mentors, and used them to destroy physically the cultural underpinnings of the Khmer civilization and to impose a new society through purges, executions, and violence.

[102] The killing of about 50–70% of Cambodia's working-age men led to a shift in norms regarding the sexual division of labor and correlates with present-day indicators of women's economic advancements and increased representation in local-level elected office.

[106] Due to the fact that the perpetrators and the victims of the mass murder were largely members of the same ethnic group, the term autogenocide was coined to describe the unique character of the genocide.

These conflicting opinions exist because scholars who conducted research in Cambodia immediately after the fall of the Khmer Rouge regime in 1979 claimed that the victims could have been killed due to the circumstances which they were living under.

"[120] On top of that, Etcheson has also proven that as a result of the systematic and mass killings which were based on political affiliations, ethnicity, religion, and citizenship, a third of Cambodia's population perished, so the Khmer Rouge is effectively guilty of committing genocide.

[124] Ben Kiernan makes the argument that it was indeed a genocide and he disagrees with these three scholars, by bringing forth examples from the history of the Cham people in Cambodia, as did an international tribunal finding Nuon Chea and Khieu Samphan guilty of 92 and 87 counts of said crime respectively.

As a result, the accounts of those Cham who experienced the repressions prior to 1975 were not considered parts of the genocide[citation needed], mainly because according to the Article 1 of the Law on the Establishment of the Extraordinary Chambers, jurisdiction ratione temporis is limited to the period from 17 April 1975 to 6 January 1979.

[149] Similarly, in June or July 1975, the Khmer Rouge authorities in Region 21 of the Eastern Zone tried to confiscate all copies of the Qur'an from the people, and at the same time, they tried to impose a mandatory short haircut on Cham women.

Third, the Cham were dispersed from their communities, they were either forced to perform labour in the fields or they were accused of plotting to incite acts of resistance or rebellions against the Khmer Rouge and arrested.

Many children had fled the Khmer Rouge without a means to feed themselves and believed that joining the government forces would enable them to survive, although local commanders frequently denied them any pay.

[174] In a hospital of Kampong Cham province, child medics cut out the intestines of a living non-consenting person and joined their ends to study the healing process.

[173] Witness at Tribunal hearing also disclosed that in Tbong Khmum province, he saw a medical staff at the hospital carrying out experiments on the wives of arrested cadre at night, when it was quiet.

The United States had avoided describing Khmer Rouge atrocities as genocide until 1989, claiming it was "counterproductive to finding peace" and only approved capturing and holding a trial for Pol Pot in 1997.

The Director General of the Foreign Service, Genta Hawkins Holmes, directed Dr. Stanton back to Washington, DC and assigned him to the Office of UN Political Affairs in the Bureau of International Organizations, with the mandate to deal with the aftermath of the Rwandan genocide.

In 1997, Cambodia's two Co-Prime Ministers wrote a letter to the Secretary-General of the United Nations requesting assistance to set up trial proceedings against the senior leaders of the Khmer Rouge.

She established the Cambodian government Task Force to plan creation of the Extraordinary Chambers in the Courts of Cambodia (ECCC), commonly called the Khmer Rouge Tribunal.

[6] But after he ousted his domestic rivals in a bloody factional coup d'état in July 1997, prompting outrage in the West, China immediately recognized the status quo and offered military aid.

"[204] During the visit, Jiang met with Norodom Sihanouk and Cambodian Prime Minister Hun Sen, signing an agreement to offer US$12 million in aid to Cambodia.

"[10] In 2009, during the court trials of some of the former Khmer Rouge leaders, Chinese Foreign Ministry spokeswoman Jiang Yu claimed: "For a long time China has ... had normal and friendly relations with previous Cambodian governments, including that of Democratic Kampuchea.