Emperor Mu of Jin

Emperor Mu of Jin, personal name Sima Dan, lived from 343 to 10 July 361 and was an emperor of the Eastern Jin dynasty. He was the only son of Emperor Kang and succeeded to the throne as an infant in 344 after his father fell gravely ill, on the advice of the official He Chong. Although he reigned for about seventeen years, real power lay with others during most of that time: first his mother Empress Dowager Chu, who acted as regent with He Chong and Sima Yu, the Prince of Kuaiji, and later officials such as Yin Hao and the general Huan Wen. His reign saw Jin territory temporarily reach its greatest extent since the loss of northern China, after Huan Wen conquered Cheng-Han in 347 and the collapse of Later Zhao let Jin regain much of the land south of the Yellow River. Later campaigns north under Yin Hao failed. He died in July 361 without a son.