The Khmer Rouge (or Red Khmer) were a group of Cambodian Communists led by radical Marxist leader Pol Pot (1925–1998). Between 1970 and 1975 the Khmer Rouge guerrilla force, supported by Communists from neighboring Vietnam, waged a war to topple the U.S.-supported government of Lon Nol (1913–1985). On April 16, 1975, Lon Nol’s regime fell, and the next day the Khmer Rouge seized the Cambodian capital, Phnom Penh. The ruthless revolutionary leader Pol Pot became prime minister of a Communist Cambodia and instituted a reign of terror. In his attempt to turn Cambodia into an agriculture-based society, the Khmer Rouge systematically emptied the cities, forcibly moving the people onto collective farms where they performed hard labor. Anyone thought to be opposed to the Khmer Rouge was killed. An estimated 2 million people died—by execution, overwork, and starvation. Pol Pot’s “experiment” had failed, and his efforts to revolutionize Cambodia amounted to nothing short of genocide.

A Vietnamese invasion ousted the Khmer Rouge in 1979 and installed a new leadership. But civil wars were fought throughout the 1980s. The warring factions, who had made various alliances among themselves, finally signed a peace treaty in 1991. Under the watchful eye of the United Nations, elections were held in 1993. The resulting constitution provided for a democratic government with a limited monarchy. At that point, the Cambodian leadership seemed to come full circle—with Norodom Sihanouk (1922-) being crowned king in 1993: In 1970 Sihanouk had been deposed by Lon Nol, whose regime later became the target of the Khmer Rouge. During his lifetime Sihanouk made strides in establishing Cambodia’s independence, and he enjoyed great public support. Due to failing health, he abdicated the throne in November 2004 and was succeeded by his son, Norodom Sihamoni (1953-).

For decades after Pol Pot was deposed, he continued to lead a revolutionary force of the Khmer in Cambodia, though he remained out of public view. His own men turned against him in early 1998, and Pol Pot died in April of that year. In December the last main fighting force of the Khmer Rouge surrendered to the Cambodian government. The event was broadcast on national television. Though some Khmer leaders remained in hiding and small bands of guerrilla fighters were thought to still exist, the radical Marxist group, which had terrorized Cambodia, no longer presented a threat to the government.