Heng Samrin (hĕng säm´rĬn), 1934–, Cambodian politician. He was president of Cambodia from 1979 to 1991 and headed the Communist party from 1981 to 1991. A regimental commander of the Khmer Rouge during the civil war (1970–75), he sought refuge in Vietnam from Pol Pot's purges (1977). Returning to lead the uprising, he was named president of the Vietnamese-installed Cambodian government after Pol Pot's overthrow (1979). He faced continued armed resistance from the Khmer Rouge and other forces and failed to gain widespread diplomatic recognition. In 1985 he lost power to Hun Sen, the new premier, but he remained head of state until Norodom Sihanouk's return in 1991.