Zhang Zuo (; died 355), courtesy name Taibo (), formally Prince Wei of (Former) Liang () was a ruler of the Chinese state Former Liang. He was the only ruler of Former Liang to formally declare a break from Jin Dynasty (266–420), and historical sources variously report him as having declared himself an emperor (per Jin Shu) or a prince (per Zizhi Tongjian). He was commonly viewed as a usurper (having seized the throne from his nephew Zhang Yaoling after his brother Zhang Chonghua's death) and initially not acknowledged as a Former Liang ruler, but his brother Zhang Tianxi later nevertheless gave him the posthumous name of Wei. During the reigns of Zhang Chonghua and Zhang Yaoling Little is known about Zhang Zuo's personal background, other than that he was Zhang Jun's oldest son, but was not designated heir apparent. His younger brother Zhang Chonghua was, even though neither was born of Zhang Jun's wife Princess Yan. Neither his mother nor his birth year was recorded in history. He was praised for being strong, brave and knowledgeable, and either Zhang Jun or Zhang Chonghua created him the Marquess of Changning. During the reign of his brother Zhang Chonghua, Zhang Zuo was trusted by his brother, and despite warnings by Chang Ju () and Xie Ai, Zhang Chonghua, for a long time, intended for Zhang Zuo to serve as regent for his son Zhang Yaoling. Late in 353, however, as Zhang Chonghua was gravely ill, he ordered that Xie be recalled to be warrant—but Zhang Zuo and Zhang Chonghua's attendants Zhao Zhang () and Wei Qi (), who had conspired to take over power, blocked Zhang Chonghua's order and instead forged an order making Zhang Zuo regent. Zhang Chonghua soon died, and he was succeeded by Zhang Yaoling, at age nine, but real power was in Zhang Zuo's hands. Zhang Zuo, who had by this point engaged in an affair with Zhang Chonghua's mother Princess Dowager Ma, soon made his move to formally take over. With Princess Ma's approval, Zhang Yaoling was deposed in early 354 and replaced with Zhang Zuo, who soon showed his cruel side, as he put Xie Ai and Zhang Chonghua's wife Princess Pei to death. Reign Early in 354, Zhang Zuo declared a clear break from Jin—a move that none of his predecessors had dared to do. He completely repudiated the Jin era name Jianxing (declared