The Cambodian Civil War ends and the Cambodian Genocide begins. The Khmer Rouge captures the capital Phnom Penh and Cambodian government forces surrender.

The Cambodian Civil War was a civil war in Cambodia fought between the Khmer Rouge, supported by North Vietnam and China, against the government of the Kingdom of Cambodia and, after October 1970, the Khmer Republic, which had succeeded the kingdom after a coup, both supported by the United States and South Vietnam. The conflict was part of the Vietnam War.