Before World War II, Cambodia was a heavily taxed, relatively quiet corner of the French empire. Its population was 80 percent Khmer, 80 percent Buddhist, and 80 percent rice-growing peasants. Up to a fifth of the population were ethnic and religious minorities: Vietnamese, Chinese, and Muslim Chams worked mostly in rubber plantations or as clerks, shopkeepers, and fisherfolk, while a score of small ethnolinguistic groups, such as the Jarai, Tampuan, and Kreung, populated the upland northeast.

After Japan’s defeat in World War II, the reimposition by force of French colonial control of Indochina provoked armed nationalist resistance by both Viet Minh and Khmer Issarak (“independence”) forces. Protracted anti-colonial conflict in both Vietnam and Cambodia fostered the emergence by 1951 of a Vietnamese-sponsored Cambodian communist movement, the Khmer People’s Revolutionary Party (KPRP), which won increasing though not unchallenged preeminence among Issarak nationalists contesting French control of their country. 1 KPRP members, led by former Buddhist monks, slowly gained leadership of the nationwide Khmer Issarak Association, which adopted for its flag a silhouette of Angkor Wat’s five towers on a red background. One faction of the independence movement initially called itself “Democratic Kampuchea”—the title later used by the Pol Pot regime as the official name of its Khmer Rouge state. 2 An anti-KPRP grouping used for its flag a three-towered motif of Angkor, the future flag of Democratic Kampuchea. Members of another anticommunist splinter group carried out racist massacres of ethnic Vietnamese in 1949, and of Chams in 1952. 3 Saloth Sar, then a student in Paris calling himself the “Original Khmer,” returned home in 1953 and briefly served in the communist-led Issarak ranks. He later assumed the nom de guerre Pol Pot.