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The Rise of the Khmer Rouge
The Cambodian communist movement emerged from the struggle against French colonization in the 1940s and grew stronger during the First Indochina War. The movement received support and training from Vietnamese communists, though this relationship later became a source of tension. During the 1950s, Cambodian students studying in France embraced communist ideas and returned home to join the underground movement. Among them was Saloth Sar, later known as Pol Pot, who became the party's secretary in 1963.
Prince Sihanouk's government increasingly repressed left-wing activists during the 1960s, forcing communists into the jungle. In March 1970, while Sihanouk traveled abroad, the National Assembly voted him out of power. General Lon Nol established the Khmer Republic with U.S. support. This change allowed wider American military operations inside Cambodia. In the final months of the war, American bombing intensified. In just seven months in 1973, before Congress halted the campaign on August 15, American aircraft dropped 250,000 tonnes of bombs on Cambodia. Many people who lost family members in the bombing joined the Khmer Rouge revolution.
After the coup, China encouraged Sihanouk to form an alliance with the Khmer Rouge. His call for Cambodians to support the communists significantly strengthened the movement. By early 1973, the Khmer Rouge controlled approximately 85 percent of Cambodian territory. As the United States lost the Vietnam War, the Lon Nol government collapsed. Khmer Rouge forces entered Phnom Penh on April 17, 1975, ending five years of civil war.
Evacuation and Year Zero
The Communist Party of Kampuchea kept its existence secret, calling itself "Angkar Padevat" (the Revolutionary Organization). Within hours of taking Phnom Penh, the Khmer Rouge ordered the entire population to evacuate. Soldiers told people the United States would bomb the city and that food shortages required everyone to move to the countryside. The evacuation had actually been planned since the early 1970s as part of the party's plan for total transformation.
Approximately two million people left Phnom Penh and other cities. Everyone, including hospital patients, the elderly, and pregnant women, had to leave immediately. Thousands died during the evacuation from exhaustion, lack of medicine, and harsh conditions. The regime executed soldiers and officials from the Lon Nol government immediately. Foreigners were ordered out of the country. Phnom Penh became known as a "ghost town," with only a few thousand people remaining to operate essential factories and guard foreign embassies.
Pol Pot and the Khmer Rouge leadership promoted a vision of Cambodia returning to "Year Zero." They believed they could recreate the greatness of the Angkor period through collective agricultural production. The regime claimed that if Khmers could build Angkor Wat, they could accomplish anything through revolutionary will and self-reliance. The party sought to create a classless society by eliminating all social distinctions except between "old people" (those who had lived in Khmer Rouge zones before 1975) and "new people" (those from cities and Lon Nol-controlled areas).
Life Under Democratic Kampuchea
Once relocated to the countryside, people of all backgrounds became agricultural workers. The regime aimed to produce three tons of rice per hectare, three times per year. This goal required building extensive irrigation systems through forced labor. The party organized the population into work brigades that operated in military fashion. People worked twelve to fifteen hours daily, digging canals, building dams, and cultivating rice fields. In some regions they worked even longer.
The Communist Party abolished money, markets, private property, formal schooling, and religious practices. Everything belonged to Angkar Padevat. Temples, schools, and government buildings were closed or converted into prisons, storage facilities, and animal farms. People throughout the country, including party leaders, wore black clothing as their revolutionary uniform. The regime prohibited all leisure activities and restricted travel. If three people gathered to talk, they risked an accusation of being enemies.
The party heavily criticized family relationships. People could not show affection, humor, or sympathy. The regime demanded that all Cambodians consider Angkar their only "mother and father." From January 1977, children aged eight and older were separated from their parents and placed in labor camps. The regime believed children could be easily shaped into loyal revolutionaries, free from the "corrupt" influence of adults and traditional values. Children received ideological training and some became members of special units that reported adults for violations of party rules.
While the regime exported rice to obtain weapons, the population received minimal food rations. Most people ate only watery rice porridge once or twice daily. Many tried secretly to supplement their diet with roots, leaves, insects, and any other food they could find. Hundreds of thousands died from starvation. Working conditions, combined with inadequate food and lack of medical care, caused widespread disease. People died from malaria, dysentery, and other preventable illnesses.
The Khmer Rouge forced people into marriages to increase the population and ensure the next generation of revolutionaries. The regime organized mass wedding ceremonies where couples who had never met were married under threat of punishment. When people refused to consummate these forced marriages, they faced severe consequences. According to research by the Women and Transitional Justice in Cambodia Project more than 96 percent of surveyed survivors experienced forced marriage, and over 80 percent were sexually assaulted after the ceremonies.
The Security State and Purges
The regime operated an extensive network of security centers to identify and eliminate perceived enemies. S-21 prison (also known as Tuol Sleng) in Phnom Penh, formerly a high school, served as the central facility. The prison held approximately 14,000 prisoners during its operation. Prisoners were photographed, interrogated under torture, and forced to confess to working for foreign intelligence agencies. Only about twelve people survived S-21. The Documentation Center of Cambodia has identified over 20,000 mass grave sites throughout the country associated with the Khmer Rouge security apparatus.
The party defined "enemies" in sweeping categories. Anyone who had served in previous governments faced execution, along with their family members. Teachers, students, and other "intellectuals" were targeted because education itself was considered corrupting. People who had been merchants or vendors were classified as "capitalists." Those who expressed affection for Prince Sihanouk were labeled "feudalists." Simply wearing glasses could mark someone as an intellectual deserving death.
Beyond these classifications, people were executed for minor offenses. Unauthorized possession of food, traveling between villages without permission, or failing to work on the correct side of a plow could result in execution. The regime demanded total control over every aspect of life. Any deviation from party expectations could be interpreted as enemy activity.
As suspicions grew within the Communist Party, the regime turned against its own members. Party cadres and their families were arrested and sent to S-21, where they confessed under torture to elaborate conspiracies. Regional purges intensified in 1977 and 1978. The party executed the leadership of the Eastern Zone, suspecting them of Vietnamese sympathies. Many cadres fled to Vietnam rather than face arrest. This pattern of internal purges continued until the regime's collapse.
Children played a complex role in the system of control. The regime used children as spies to report on adults, including their own parents. Some children rose to positions of authority in work camps by age twelve. Survivors recall that camps run by children often experienced extreme violence. The party believed children represented purity and revolutionary potential, untainted by Cambodia's past.
Cultural Destruction
The Khmer Rouge systematically destroyed Cambodia's cultural heritage. The regime banned all traditional practices, including Buddhist ceremonies, festivals, and artistic performances. Temples were demolished or converted to other uses. The University of Fine Arts closed. There was no formal education in art, music, or dance. When performances did occur, they served only as propaganda for the party.
The targeting of artists, musicians, and dancers proved particularly devastating. According to estimates, approximately 90 percent of Cambodia's artists perished during the regime. Of 190 ballet artists before 1975, only 40 survived. The Ministry of Information and Culture later reported that of roughly 3,000 members of the Khmer Association of Artists in 1975, only about 10 percent remained alive in 1979. Master musicians who had spent their entire lives perfecting traditional arts were executed or died from the harsh conditions.
This cultural destruction extended beyond individual artists. The knowledge, techniques, and traditions they carried largely disappeared with them. Musical instruments were destroyed. Dance costumes and masks were lost. The few surviving artists faced the challenge of reconstructing entire performance traditions from memory after 1979.
Fall of the Regime and Immediate Aftermath
Relations between Democratic Kampuchea and Vietnam deteriorated throughout the regime. Border clashes occurred as early as 1975, but large-scale fighting began in 1977. Pol Pot, fearing Vietnamese domination, ordered attacks into Vietnamese border provinces. The Vietnamese army retaliated, penetrating deep into eastern Cambodia.
In December 1978, Vietnamese forces invaded Cambodia. They captured Phnom Penh on January 7, 1979. Khmer Rouge leaders fled westward to the Thai border. Even on the final morning before the Vietnamese arrival, executioners at S-21 killed fourteen more prisoners. The discoverers of the prison were alerted to its existence by the smell of decaying bodies.
The Documentation Center of Cambodia's mapping project provides the most comprehensive data on the death toll. Through a systematic survey of mass graves across the country, researchers have documented more than 1.1 million victims of execution. Demographic studies suggest that deaths from execution represented approximately 30 to 50 percent of all deaths during the regime, with the remainder caused by starvation, disease, and overwork. The total death toll reached between 1.7 and 2 million people out of a population of approximately 7 million.
Those who survived faced a country in ruins. A severe famine struck Cambodia in 1979 and 1980. Temples lay destroyed. Cities remained empty, with homes ransacked and abandoned. Survivors faced the agonizing task of searching for family members, often learning that loved ones had perished. Most people with skills needed to rebuild the country's economic, social, and cultural infrastructure had been killed or had fled abroad. The psychological trauma affected virtually the entire population, with effects that persist across generations.
International Response and Justice
Foreign journalists who witnessed the Khmer Rouge takeover of Phnom Penh wrote about the atrocities they observed. After the regime sealed off the country, reports continued to emerge from refugees fleeing to Thailand. Western journalists interviewed refugees and heard accounts of widespread executions, disease, and starvation. The United States government had detailed knowledge of the regime's brutal policies as early as 1976. A memo from National Security Advisor Brent Scowcroft to President Ford showed specific information about forced relocations and the transformation of Cambodia.
However, the international community took little action while the crimes were occurring. The United States, fresh from defeat in Vietnam, remained reluctant to intervene in Southeast Asia. In April 1978, President Carter declared the Khmer Rouge "the worst violator of human rights in the world today," but his administration took no steps to stop the ongoing atrocities.
After Vietnam overthrew the Khmer Rouge, a bizarre political situation emerged. The People's Republic of Kampuchea, backed by Vietnam, became the de facto government but lacked international recognition. The United Nations continued to recognize the Khmer Rouge as Cambodia's legitimate representative until 1991. China and several Western nations provided support to a coalition that included the Khmer Rouge, united primarily by opposition to Vietnam. This meant the perpetrators of mass atrocities retained their international standing for more than a decade after their crimes.
Only in 2006, after years of negotiations, did the Extraordinary Chambers in the Courts of Cambodia begin operations to prosecute surviving Khmer Rouge leaders. The tribunal has convicted several senior leaders of crimes against humanity and genocide. The Documentation Center of Cambodia, founded by a survivor, has preserved more than one million documents from the regime. These efforts at justice and documentation continue, though they came decades after the crimes occurred and many perpetrators have died.