Khieu Samphan (born July 27 1931) was the Prime Minister of Cambodia and chairman of the state presidium from 1976 until 1979. He was one of the most powerful officials in the Khmer Rouge government, though Pol Pot was the real leader of the movement. After the fall of the Khmer Rouge in 1979, Samphan led a rebel government which maintained some international recognition until 1982. In 1985 he officially succeeded Pol Pot as leader of the Khmer Rouge, and served in this position until he surrendered to the Cambodian government in 1998.