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The Rise and Fall of Democratic Kampuchea

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Cambodia, a small Southeast Asian country of about fifteen million people, is generally known to the outside world for its two seemingly contrasting historical episodes, namely the great civilization during the Angkorean period and the more recent bloody Khmer Rouge regime.

Image of crowds of peopleHome to the Angkor Wat Temple, considered the largest religious edifice in the world, Cambodia was once the Khmer Empire, which dominated most of mainland Southeast Asia during the twelfth and thirteenth centuries. The eventual rise of Siam (now Thailand) and Việt Nam as powerful neighbors helped perpetuate the decline of Cambodia. By the early nineteenth century, Cambodia had become a tributary state to both Siam and Việt Nam. In 1863, Cambodia became a French protectorate (and eventually a colony), which would last for ninety years. The French served as a power to relinquish Siam’s and Việt Nam’s control over Cambodia, regain some former Cambodian territories, and restore the famous Angkor ruins. The French also introduced modern infrastructure and an educational system in the country, albeit at a much slower pace compared to their activities in French-ruled Cochin-China (southern Việt Nam). They did little to create a liberal ruling system for Cambodia, and indirectly, the French presence helped foster the emergence of a communist movement in the country.

. . . Sihanouk believed that communists in the region would win the war. He collaborated with China, and eventually had a secret alliance with North Viêt Nam, with the intention of keeping Cambodia out of the war and keeping himself in power.

The saddest episode of Cambodian history and certainly one of the greatest tragedies in the history of mankind occurred in Cambodia between 1975 and 1979, when the country (renamed Democratic Kampuchea) was ruled by a group of Cambodian communists that became infamous under the unofficial name of the “Khmer Rouge.” Once in power, the leaders of Democratic Kampuchea (DK) embarked on a bloody revolution that resulted in the deaths of at least 1.7 out of seven million people from starvation, inhumane working conditions, disease, and execution. The essay that follows is an introduction to the saga of DK.


To understand how the Khmer Rouge came to power in Cambodia in 1975, it is imperative to look at the domestic and international politics of the time, as well as the major actors who shaped and influenced the political developments in Cambodia and in the region.

Two years after helping Cambodia gain independence from France in 1953, King Norodom Sihanouk of Cambodia abdicated the throne in favor of his father, and pursued his political ambition by founding the Sangkum Reastr Niyum (usually translated as “People’s Socialist Community”). Sihanouk claimed that the Sangkum was not a political party, but those who wished to join were required to relinquish their membership from other political parties. Thanks to his popularity among Cambodian peasants and suppression of other political parties, Sihanouk managed to win a landslide majority in the 1955 election. His ascendance to real power marked the decline of the hitherto popular Democratic Party, as well as increasing repression of communists inside the country, who were eventually driven underground. By 1967, all communists present in Sihanouk’s government left their official posts to join their colleagues in the jungle.

Likewise, the international situation made it difficult for Cambodia to remain neutral. Following Cambodian independence, French Indochina became a hotbed for the Cold War. The Việt Nam War was to become a great entanglement for the United States in the region. Believing in the “domino theory,” the US did not wish to see Southeast Asia fall to communism. Despite declaring neutrality, Cambodia was geopolitically trapped, and soon dragged into the war.

Photo from left Mao Zedong, Peng Zhen, King norodom Sihanouk, and Liu Shaoqi.
Meeting in Beijing: from left Mao Zedong, Peng Zhen, King norodom Sihanouk, and Liu Shaoqi.
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While suppressing Cambodian communists within Cambodia, Sihanouk believed that communists in the region would win the war. He collaborated with China, and eventually had a secret alliance with North Việt Nam, with the intention of keeping Cambodia out of the war and keeping himself in power. In 1963, Sihanouk decided to cut off US economic and military assistance, which had totaled about US $404 million since the country gained independence. Moreover, he nationalized Cambodia’s banks and the country’s export-import trade. By 1964, Cambodia broke off relations altogether with the United States, and turned to China for an international alliance.1 In doing so, Sihanouk alienated the right wing of his government (especially the army) who had benefited from American aid. More importantly, he angered Cambodian nationalists by secretly allowing the Vietnamese communists to establish sanctuaries inside Cambodian territory. Students and intellectuals in the city were increasingly disillusioned with unemployment and his mishandling of the economy.

In March 1970, while Sihanouk was abroad, the National Assembly voted him out of power and sentenced him to death in absentia. After almost two thousand years, monarchy was officially abolished for the first time in Cambodia. The Khmer Republic under General Lon Nol was proclaimed with the support of the US. This paved the way for wider scale US bombing of Vietnamese communists inside Cambodian territory, which had already begun in 1969 under President Nixon.2 For a period of four years, US bombing of Cambodia totaled more than half a million tons of explosives, exceeding the amount of bombs dropped by the Allies on Japan throughout World War II, and causing, at the very least, over 150,000 casualties.3 While the bombing temporarily prevented the communist victory in Cambodia, it also drove many peasants to the jungle, thereby strengthening the communist forces.

The mid-1950s marked the return of a number of Cambodian students from France, who had already embraced communism in France. . . . Saloth Sar, better known as Pol Pot, the future leader of DK, was one of them.

A man (Pol Pot) is speaking
Pol Pot addresses a closed meeting in Phnom Penh after the 1975 Khmer Rouge victory.
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Cambodian communists had been closely linked with (and relied on) communist movements in Việt Nam to fight French colonialism. As early as the 1940s, there were a number of Cambodian members in the Vietnamese-controlled Indochinese Communist Party (ICP). In 1951, the Khmer People’s Revolutionary Party (KPRP) was founded. In theory, the Cambodian and Vietnamese communist movements were supposed to be on equal terms. In practice, every decision was made by the Vietnamese communists, who viewed their Cambodian counterparts as incompetent. This arrangement worked well to remind the Cambodians of Vietnamese control over Cambodia in the past, which Cambodians resented.

The mid-1950s marked the return of a number of Cambodian students from France, who had already embraced communism in France. Unlike their Vietnamese-trained counterparts, these Cambodians were more nationalist and also unhappy with Vietnamese tutelage of Cambodian communists. These new Cambodian communists led purges of pro-Vietnamese cadres. The returnees from France were mostly intellectuals who received scholarships from the Cambodian government to study there. By the early 1950s, they concerned themselves mainly with winning the country’s independence from France. Saloth Sar, better known as Pol Pot, the future leader of DK, was one of them. Upon their return, they became teachers and worked clandestinely for their revolution. During the 1960s, Sihanouk’s repression of the left eventually pushed all Cambodian communists into the jungle, from where they would lead their revolution. With the intensification of US bombing, the Khmer Rouge army gained more local support and became more fierce. After the 1970 coup, with China’s urging, Sihanouk formed a tactical alliance with the Khmer Rouge believing that they could bring him back to power. Undoubtedly, Prince Sihanouk’s call for his people to join the Khmer Rouge did much to strengthen them. As the US was losing the Việt Nam War, the corrupt Khmer Republic eventually collapsed when the Khmer Rouge entered Phnom Penh on April 17, 1975.


Many people initially greeted Khmer Rouge soldiers with joy, believing that peace had finally arrived. Before long, they would find themselves walking into a living hell. Pol Pot had envisioned a totally new, classless, and self-independent society, in which the peasants were regarded as the backbone of the society. He reputedly claimed that if the Khmers could build Angkor, they could do anything. Cambodia was to be started anew, at Year Zero.

As soon as they took over Phnom Penh, the Khmer Rouge ordered all citizens to evacuate to the countryside on the pretext that the US would bomb the city, and that there were food shortages for the overcrowded urban population. In fact, potential bombings by the US and food shortages were not the whole story. Pol Pot and the Khmer Rouge leadership had been planning Phnom Penh’s evacuation since the early 1970s as part of their ideological scheme of a total communist revolution. Foreigners were ordered out of the country. Soldiers and officials of the Khmer Republic were immediately executed. Everybody, young and old, sick or not, was ordered to leave the city immediately to engage in agricultural activities. For many, the journey would become a trail of death. Patients died for lack of drugs; pregnant women delivered babies on the way, if they managed to survive. The capital was almost entirely vacated, with the exception of a few factories and a number of embassies of countries friendly to the Khmer Rouge, including China and Yugoslavia. Many schools were turned into animal farms or prisons, the most infamous of which was S-21 (formerly Tuol Svay Prey high school). Houses and shops were emptied; cars piled up on the streets. Phnom Penh came to be known as a “ghost town” during Khmer Rouge rule.

People who knew Pol Pot in the early days had little inkling of the person he would turn out to be. Even during his first year in Paris, Pol Pot was known as someone who “liked to have fun.” His reading of Stalin and Mao later probably influenced his revolutionary conviction, along with other factors, including the hard days in the jungle, the destruction of Cambodia from the war, and his vision of Cambodia’s glorious Angkorean past—which caused Pol Pot to emphasize “independence-mastery.”

Once the population was relocated to the countryside, people of all professions were to become farmers engaging mainly in rice production and building dams and irrigation systems in order to meet the communist party’s goal of producing three tons of rice per hectare, three times a year. By doing so, the leaders of DK also aimed to create a classless society, although in reality, those who joined the revolution before 1975 were relatively better off. Religion, the market economy, and family ties were all abolished. Everything belonged to Angkar Padevat (or the “revolutionary organization”), which was “righteous and enlightened” in carrying out the revolution that the entire population was expected to pursue with complete dedication.

While rice was exported abroad in exchange for military weapons, people were left with virtually nothing to eat and had to work the whole day but had only watery rice porridge to eat. Many people secretly tried to supplement their diets by eating roots, leaves, and insects. Hundreds of thousands of people died of starvation, overwork, and/or disease. However, suffering varied according to region and chronology. Life in the Eastern Zone was relatively better than in the Western and Southeast Western Zone. Also, food provision was slightly better before 1977, when Democratic Kampuchea began their border attacks on Việt Nam.

Image of S-21 prison building
S-21 prison. Image source: Right: S-21 prison torture room. Image source: Photo by Bruce Sharp

Image of S-21 prison torture room with a bed framePURGING THE ENEMIES

As in other communist regimes, the DK leaders were highly suspicious of enemies from within and sought to crush them at all costs. The notorious prison, S-21 (known to Cambodians as kuk Tuol Sleng), was considered a place where people “entered but never returned.” Khmer Rouge cadres and their family members who were arrested usually “confessed” under torture to working for the CIA or KGB.4

DK’s relations with Việt Nam continued to deteriorate. What caused the conflicts were not their ideological differences, but mainly Pol Pot’s fear of Việt Nam’s geopolitical hegemony. Despite, or perhaps because Pol Pot had received training from the Vietnamese, he was increasingly intolerant of Việt Nam’s perceived domination. Pol Pot’s cynicism became stronger after July 1977, when Việt Nam signed a treaty of cooperation with Laos. Clashes between the Khmer Rouge and Vietnamese forces over ownership of some islands in the Gulf of Thailand and along the border took place as early as 1975. But the Khmer Rouge, believing that China would support their cause, began large-scale attacks in mid-1977 into bordering Vietnamese provinces with the intention of gaining back Cambodian territories lost to the Vietnamese a few centuries ago. The Vietnamese army retaliated and penetrated as deep as thirty-two kilometers into eastern Cambodia.

Already fearing a possible revolt, DK leaders suspected that the Eastern Zone cadres were siding with the Vietnamese. They were accused of having kbal yuon kluon khmer (Khmer bodies with Vietnamese heads). Pol Pot ordered a series of executions of the Eastern Zone cadres, many of whom were also brought to S-21. The leader of the Zone—So Phim—committed suicide in 1978 after he received an invitation to Phnom Penh from Pol Pot.5 Other Khmer Rouge cadres fled to Việt Nam and later joined the Vietnamese army in overthrowing Democratic Kampuchea.

Democratic Kampuchea finally collapsed when the People’s Army of Việt Nam (PAVN) and the Kampuchean United Front for National Salvation (KUFNS), comprising former Khmer Rouge cadres and Cambodian communists exiled in Việt Nam, took over Phnom Penh on January 7, 1979. Even so, the executioners of S-21 managed to take the lives of fourteen more victims on the morning of January 7, before their final escape. So many people lost their lives at S-21 (at least 12,000) that the foreign discoverers were alerted to its existence by the stench of decaying bodies coming from an enclosed compound behind an iron fence.6

Even out of power, the Khmer Rouge remained a threat to Cambodia for several more years. Despite being the de facto Cambodian government during the 1980s, the People’s Republic of Kampuchea (PRK), which was backed and supervised by Việt Nam, was not recognized by the United Nations. Only Việt Nam, Laos, the Soviet Union, and its allies considered the PRK a legitimate government. India was the only non-communist country to do so. The geopolitical environment created a bizarre situation in which the Khmer Rouge retained their UN seat, in spite of their widely known atrocities. In 1982, China and the Association of Southeast Nations (ASEAN) countries pressured the Khmer Rouge to form an alliance with Sihanouk’s forces and other republicans led by Son Sann along the Thai border, calling it the Coalition Government of Democratic Kampuchea (CGDK) under the presidency of Norodom Sihanouk. The CGDK was hardly a government, since the three factions had different bases along the Thai border and were hostile to one another. The only thing that tied them together was their anti-Việt Nam stance. Nonetheless, CGDK was the legitimate government at the UN and remained so until 1991.

The notorious prison, S-21 (known to Cambodians as kuk Tuol Sleng), was considered a place where people “entered but never returned.”

During the 1980s, the Khmer Rouge, more often than the other two groups, would lead guerilla warfare against the Vietnamese-backed PRK, while people in Cambodia were only slowly recovering without substantial international aid. A few hundred thousand refugees also fled to the Thai border because international aid poured in faster, but also out of frustration with another socialist regime in Cambodia.

Only with the signing of the Paris Peace Agreement in October 1991, following the Vietnamese withdrawal from Cambodia, did peace slowly return to the country. The United Nations Transitional Authority in Cambodia (UNTAC) was established as a peacekeeping force to ensure a free and fair election in 1993. Contrary to the agreements, however, the Khmer Rouge refused to disarm, because they believed there were still disguised Vietnamese troops inside Cambodia. The Khmer Rouge then boycotted the UN-sponsored 1993 election. Retreating to western and northern parts of Cambodia, the Khmer Rouge was outlawed in 1994. The end of the Cold War meant that support for the Khmer Rouge drained out. Eventually, Ieng Sary (DK foreign minister), Khieu Samphan (DK head of state), and Noun Chea (president of DK national assembly) surrendered to the government along with most Khmer Rouge troops, who were incorporated into the Royal Cambodian Armed Forces. Pol Pot was arrested by his own commander-in-chief, Ta Mok, and died under house arrest in 1998. Ta Mok was captured the following year and died in custody in 2006. The Khmer Rouge resistance movements effectively ended.

Screenshot of Kaing Guek Eav's case page
Extraordinary Chambers in the Courts of Cambodia case page for Kaing Guek Eav (alias ”Duch“).

In 2006, after a series of negotiations with the United Nations, the Royal Government of Cambodia approved the establishment of the Extraordinary Chambers in the Courts of Cambodia (ECCC, aka. Khmer Rouge Tribunal), to bring to trial the surviving top leaders of Democratic Kampuchea. Those who have been named thus far are: Ieng Sary, his wife Ieng Thearith (DK minister of Social Affairs), Khieu Samphan, Noun Chea, and S-21’s director Kaing Guek Eav (alias “Duch”). With the exception of Duch, other leaders of DK have pleaded not guilty. Meanwhile, the ECCC has suffered from financial freezes over allegations of corruption within the institution.7 Likewise, while some Cambodians eagerly want to see the tribunal move forward, others show little interest in it thirty years after the crimes were committed. Recently, the ECCC has discussed bringing more Khmer Rouge leaders to trial, although Cambodia’s prime minister, Hun Sen, claimed that doing so would destroy the reconciliation process, and that he would rather see the court fail than cause civil war.

Whether or not Cambodians feel the ECCC will eventually bring justice, the legacy of Khmer Rouge rule continues to affect the country. Close to two million people died, while those who survived, in addition to their own suffering, experienced the trauma of losing family members because of Khmer Rouge atrocities. There are still landmines in Cambodia, although de-mining efforts by some organizations show encouraging signs. Cambodia has benefited from a booming economy, especially in the urban areas, but the destruction of the country’s economy, infrastructure, and human resources under the Khmer Rouge means that recovery for the country still has a long way to go.

Whatever combination of factors influenced the decisions of the leaders of Democratic Kampuchea, that regime carried out extremist and disastrous policies, and should ultimately be responsible for the destruction of Cambodia.


The geopolitical and ideological clashes of the Cold War and rivalry for regional hegemonic power helped bring about a bloody regime, and eventually its collapse, in Cambodia. Blaming outside forces is not entirely satisfactory for historical analysis, however. Whatever combination of factors influenced the decisions of the leaders of Democratic Kampuchea, that regime carried out extremist and disastrous policies, and should ultimately be responsible for the destruction of Cambodia.

Though limited in scope and detail, this essay introduces some of the factors that contributed to the Khmer Rouge accession to power, the tragedy of Cambodian history under Democratic Kampuchea rule, and some of the repercussions of Khmer Rouge rule. Fortunately, there are abundant resources to teach or learn more about the Khmer Rouge. Perhaps nothing brings a more vivid picture of life in Cambodia than the award-winning movie The Killing Fields. Besides the Genocide Studies Program at Yale University, the Documentation Center of Cambodia (DC-Cam) in Phnom Penh holds a vast collection of archives related to the regime. In 2007, a staff member of DC-Cam, Khamboly Dy, published a short book titled A History of Democratic Kampuchea (1975–1979) both in Khmer and in English.8 Philip Short’s Pol Pot: Anatomy of Nightmare, Ben Kiernan’s How Pol Pot Came to Power, and David Chandler’s The Tragedy of Cambodian History are only a few works among many others on the Khmer Rouge, that provide detailed discussion on the context in which Democratic Kampuchea took place.9


1. See John A. Tully, A Short History of Cambodia: From Empire to Survival (Crows Nest, NSW: Allen & Unwin, 2005), 143–144.

2. See William Shawcross, Sideshow: Kissinger, Nixon, and the Destruction of Cambodia (New York: Simon and Schuster, Inc., 1979).

3. According to historian John Tully, the US dropped almost 540,000 tons of bombs on Cambodia during the first half of the 1970s, exceeding the total of 160,000 tons of bombs dropped by the Allies on Japan in all of World War II. Estimates of the death toll range widely, from 150,000 to the US historian Chalmers Johnson’s perhaps inflated estimate of 750,000. Tully, A Short History of Cambodia, 165.

4. For a detailed discussion of Toul Sleng, see David Chandler, Voices from S-21: Terror and History in Pol Pot’s Secret Prison (Berkeley: University of California Press, 1999).

5. David Chandler, The Tragedy of Cambodian History (New Haven, CT: Yale University Press), 296.

6. See Milton Osborne, Phnom Penh: A Cultural History (New York: Oxford University Press), 181. For a detailed discussion of Toul Sleng, see Chandler, Voices.

7. Duch converted to Christianity after the fall of DK rule and lived with a hidden identity until he was found by British photojournalist Nic Dunlop in 1999. Duch surrendered after the publication of his interview and since then has been held in custody. He is currently being interrogated about his role as director of S-21. See Nic Dunlop, The Lost Executioner: A Journey to the Heart of the Killing Fields (London: Bloomsbury, 2005).

8. Khamboly Dy, A History of Democratic Kampuchea (1975–1979) (Phnom Penh: Documentation Center of Cambodia, 2007). Available for download at

9. See, for example, David Chandler, The Tragedy of Cambodian History and Ben Kiernan, The Pol Pot Regime: Race, Power, and Genocide in Cambodia under the Khmer Rouge, 1975–1979, second edition (New Haven, CT: Yale University Press, 2002).