《北史·本记·卷一》
十二月，晋桓玄废去晋帝司马德宗，改称为平固王，自立为帝，国号为楚。
十二月，晋桓玄废其主司马德宗为平固王而自立，僭号楚。
In December, the Jin minister Huan Xuan deposed the Jin emperor Sima Dezong, reduced his title to King of Pinggu and made himself emperor, with the reign title Chu.