Emperor Gong of Jin

Emperor Gong of Jin, personal name Sima Dewen, was the last emperor of the Eastern Jin Dynasty (266–420) in China. He became emperor in January 419 after his developmentally disabled brother Emperor An was killed by the regent Liu Yu, and during his brief reign, actual power was in Liu Yu's hands. On 7 July 420, under pressure from Liu Yu, he yielded the throne to Liu Yu, ending Jin's existence. Liu Yu founded the Liu Song dynasty, and in October or November 421, believing that the former Jin emperor posed a threat to his rule, had him asphyxiated with a blanket.