About Khieu Samphan
Khieu Samphan is a Cambodian former politician, economist, and revolutionary who was Chairman of the State Presidium of Democratic Kampuchea from 1976 until 1979. As such, he served as Cambodia's head of state and was one of the most powerful officials in the Khmer Rouge movement, although Pol Pot remained the General Secretary of the Communist Party of Kampuchea. On 7 August 2014, along with other members of the regime, he was convicted and received a life sentence for crimes against humanity during the Cambodian genocide, and a further trial found him guilty of genocide in 2018. Samphan is the oldest living former prime minister and the last surviving senior member of the Khmer Rouge following the deaths of Nuon Chea in August 2019 and Kang Kek Iew in September 2020. In April 2008, Samphan made his first appearance at the Khmer Rouge Tribunal. Once the KSA was shuttered by French authorities in 1956, he founded yet another student organization, the Khmer Students' Union. In 1966, he then became a member of a 'Counter-Government' created by Sihanouk to keep the rightists under control.
Biography source: Wikipedia. The profile adds birthday-specific historical context from the Celebs Birthday Today editorial database.