Zhang Zuo
During the reign of the violent and capricious Zhang Zuo, Song Hun served as a general, even though he constantly feared Zhang Zuo, because his older brother Song Xiu (宋修) had previously had a conflict with Zhang Zuo. In 355, when Zhang Guan rose against Zhang Zuo, Song started an uprising of his own against Zhang Zuo as well, and quickly arrived at the capital Guzang (姑臧, in modern Wuwei, Gansu). Zhang Guan's brother Zhang Ju (張琚) and son Zhang Song (張嵩) then started an uprising inside the city and opened the gates to welcome Song's forces in. Zhang Zuo's own troops turned on him and killed him. Song and Zhang Ju jointly declared Zhang Zuo's nephew, Zhang Xuanjing (whose older brother Zhang Yaoling was the legitimate ruler before Zhang Zuo seized the throne from him and killed him), the Duke of Xiping, a Jin-created title that his ancestors had carried for generations. When Zhang Guan subsequently arrived, Zhang Guan became regent, and Song was a key assistant. Zhang Guan overruled Song's decision and had Zhang Xuanjing claim a title that Jin had never conferred—Prince of Liang.