From After the Killing Fields: Lessons from the Cambodian Genocide, by Craig Etcheson (Texas Tech U. Press, 2006), pp. 2-4 (footnote references omitted):
It is an extraordinary situation. Cambodia is a country where as much as a third of the population died in one of the worst genocides of modern times, and many Cambodians do not believe it happened. How can it be that so much destruction occurred so recently, yet so few are aware of this history? In order to explain how this peculiar situation came about and perhaps to help to correct it, we must start at the beginning of the Thirty Years War.
That war began in 1968, when the Communist Party of Kampuchea—popularly known as the “Khmer Rouge”—declared armed struggle against the government of Cambodian leader Prince Norodom Sihanouk. Over the course of this war, the conflict took many different forms, went through many phases, and involved a list of participants nearly as long as the roster of the membership of the United Nations. The country changed its name six times during the Thirty Years War, beginning as the Kingdom of Cambodia, changing to the Khmer Republic in 1970, Democratic Kampuchea in 1975, then the People’s Republic of Kampuchea in 1979, the State of Cambodia in 1989, and finally back to the Kingdom of Cambodia again in 1993. These contortions reflected the extraordinary violence of the underlying turmoil. Cambodia finally emerged from the Thirty Years War in 1999, with the capture of the last Khmer Rouge military leader still waging armed resistance.
The Thirty Years War wrought upon Cambodia a level of destruction that few nations have endured. At the epicenter of all this violence, from the beginning until the end, there was one constant, churning presence: the Khmer Rouge. Though they have now ceased to exist as a political or military organization, Cambodia continues to be haunted both by the influence of the individuals who constituted the Khmer Rouge and by the legacy of the tragedy they brought down on the country. The social, political, economic, and psychological devastation sown by the Khmer Rouge will take generations to heal, if indeed it ever can be healed. This epic saga of havoc is so complex and confusing that scholars do not even entirely agree on how to name all the ruin.
Many historians describe the conflicts in Southeast Asia during the second half of the twentieth century in terms of three Indochinese wars. The First Indochina War was the war of French decolonization in Vietnam, Laos, and Cambodia, beginning in 1946 and ending with the Geneva Conference of 1954. The Second Indochina War can be said to have run from 1954 to 1975; it is typically known in the United States as the “Vietnam War” and in Vietnam as the “American War,” a dichotomy that reveals much about who was centrally involved. In this war of Vietnamese unification, as the United States attempted to prevent the consolidation of communist rule over all of Vietnam, the war also spread to engulf both Laos and Cambodia. The Third Indochina War began hard on the heels of the second, when from 1975 to 1991, the issue of who would rule Cambodia and how it would be ruled drew deadly interest from virtually every country in the region and from all the world’s major powers.
From 1968 onward, it appeared to many Cambodians that these wars flowed from one into the other, as inexorably as the Mekong River flows into the sea. The 1991–1993 United Nations peacekeeping mission in Cambodia marked the end of the Third Indochina War, but the fighting in Cambodia continued for nearly another decade afterward. The outlines of the conflict in Cambodia changed with the United Nations intervention, but the basic issue underlying the war—the Khmer Rouge drive for power—was not resolved by the peace process. Combat continued between the central government and the Khmer Rouge until the government finally prevailed in 1999. Thus, what historians characterize as distinct wars with distinct protagonists appeared to many Cambodians to be simply one long war, with one central protagonist—the Khmer Rouge—driving the entire conflict.