The Khmer kingdoms of Cambodia flourish from the 9th to 13th centuries, reaching a high point at the end of the 12th Century, after which they undergo a gradual decline.
From the 15th Century onwards Cambodia is squeezed by the neighbouring kingdoms in Thailand and Vietnam, with both progressively encroaching on Cambodian territory. Attempts by the Vietnamese to impose their culture on the Cambodians set the seeds for an abiding distrust. The encroachment is halted in 1863 when Cambodia agrees to become a French protectorate.
When the Japanese dissolve the French administration in March 1945 the country achieves a short-lived but compromised independence lasting until the French return in October 1945, following the end of the Second World War.
Complete independence is finally granted in November 1953, with Prince Norodom Sihanouk establishing a 16-year rule based on an eclectic mix of populism, Khmer nationalism and state socialism.
The region is soon destabilised by the war in Vietnam. Sihanouk establishes ties with North Vietnam, the Viet Cong and China and distances the country from the United States, which he believes is plotting against him. In November 1963 he terminates the US aid program and in May 1965, as the war spills into Cambodia, breaks relations completely.
Meanwhile, domestic opposition to Sihanouk starts to mount. Disaffected groups begin to go underground and take up arms, including the Khmer Rouge, the radical wing of the Kampuchean Communist Party led by Saloth Sar, later to be known to the world as Pol Pot.
- Cambodia - A Country Study - Library of Congress Country Studies Series