In 712, Emperor Ruizong passed the throne to Li Longji (as Emperor Xuanzong), but, at Princess Taiping's suggestion, retained most imperial powers as "Taishang Huang" (retired emperor). In 713, after Emperor Xuanzong, claiming that Princess Taiping was planning to kill him, carried out a reprisal against her, forcing her to commit suicide and executing many of her associates, Emperor Ruizong transferred his authorities to Emperor Xuanzong. In winter 713, Emperor Xuanzong carried out a major review of troops at Xinfeng (新豐, in modern Xi'an, Shaanxi), during which, due to the ceremony not being properly organized as it was supposed to be, he removed and exiled the chancellor Guo Yuanzhen, who was also minister of defense. While at the ceremony, Emperor Xuanzong met a number of prefectural prefects, including Yao Yuanzhi, who personally made 10 suggestions of how he should govern (now known in Chinese as 十事要說), and Emperor Xuanzong considered making Yao chancellor. The chancellor Zhang Yue, jealous of Yao, initially had the imperial censor Zhao Yanzhao submit articles of impeachment against Yao, but when that failed, had the official Jiang Jiao (姜皎), a close associate of Emperor Xuanzong, suggest that Yao should be made the commandant at Hedong (河東, in modern Yuncheng) -- which made Emperor Xuanzong suspicious that Zhang was behind the recommendation, and Jiang admitted that that was the case. The next day, Emperor Xuanzong summoned Yao to his presence and made him minister of defense and chancellor with the designation "Tong Zhongshu Menxia Sanpin", and created him the Duke of Liang.