Democratic Kampuchea was the official name of the Cambodian state from 1975 to 1979, under the general secretaryship of Pol Pot and the Communist Party of Kampuchea (CPK), commonly known as the Khmer Rouge. The Khmer Rouge's capture of the capital Phnom Penh in 1975 effectively ended the United States-backed Khmer Republic under Prime Minister-later President Lon Nol.
From 1975 to 1979, the Khmer Rouge's one-party regime killed millions of its own people through mass executions, forced labour, and starvation, in an event which has come to be known as the Cambodian genocide. The killings ended when the Khmer Rouge were ousted from Phnom Penh by the People's Army of Vietnam (PAVN).