 Emperor Xuanwu died suddenly in 515.The officials Yu Zhong and Cui Guang (崔光) quickly proclaimed Emperor Xuanwu's young crown prince Yuan Xu emperor (as Emperor Xiaoming) and seized power away from Emperor Xuanwu's wife Empress Gao, whose uncle Gao Zhao, who was also Emperor Xuanwu's uncle, was extremely powerful.In order to counteract Gao Zhao, Yu and Cui forced Empress Gao to yield regent powers to Yuan Yong and Emperor Xiaowen's cousin Yuan Cheng (元澄) the Prince of Rencheng, and then, Yu and Yuan Yong ambushed Gao Zhao and killed him.