Zhangsun Wuji

Zhangsun Wuji (長孫無忌) (d. 659), courtesy name Fuji (輔機), formally Duke of Zhao (趙公), was a chancellor of the Chinese dynasty Tang Dynasty during the reigns of his brother-in-law Emperor Taizong (Li Shimin) (husband of his sister Empress Zhangsun) and nephew Emperor Gaozong (Li Zhi). He was an important assistant of Li Shimin when Li Shimin was the Prince of Qin under his father Emperor Gaozu and helped Li Shimin in killing his rivals and brothers Li Jiancheng the Crown Prince and Li Yuanji the Prince of Qi at the Incident at Xuanwu Gate, eventually enabling Li Shimin to become emperor. He was also instrumental in Emperor Taizong's selection of Li Zhi as crown prince, and was exceedingly powerful after Li Zhi took the throne as Emperor Gaozong. However, he gradually lost his nephew's favor by failing to support Emperor Gaozong's decision to depose his first wife Empress Wang and replacing her with Empress Wu. In 659, Empress Wu's political ally Xu Jingzong falsely accused Zhangsun of treason, and Emperor Gaozong exiled Zhangsun. Xu subsequently sent the official Yuan Gongyu (袁公瑜) to force Zhangsun to commit suicide.
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