 The death of Taizong set up a second succession crisis, again instigated by Empress Dowager Yingtian and fueled by the conflict between Chinese primogeniture and Khitan succession customs. Yelü Ruan, oldest son of Prince Bei and nephew of Emperor Taizong, proclaimed himself Emperor while still in Hebei. Emperor Taizong raised Yelü Ruan, following Yelü Bei's departure for the Later Tang, and the relationship between uncle and nephew was close. Yelü Ruan accompanied the emperor during his invasion of the Later Jin, and he earned the reputation as a capable warrior and commander, and as one of courteous and noble-minded disposition. Empress Dowager Yingtian supported Emperor Taizong's younger brother, Yelü Lihu, for the throne instead. The Empress Dowager sent two successive armies to face Yelü Ruan, who defeated them both. Ultimately Lihu, who the Khitan nobility viewed as cruel and spoiled, was unable to gain enough support to further challenge Yelü Ruan, and after a peace was brokered by a cousin of the Yelü clan, Yelü Ruan formally assumed the role of emperor and the title of Emperor Shizong of Liao. Emperor Shizong promptly exiled both Empress Dowager Yingtian and Yelü Lihu from the capital, ending their political ambitions. Emperor Shizong's rule would be characterized by a series of rebellions from within his extended family. Although he would rule for only four years before being killed in 951 in a rebellion led by one of his nephews, Emperor Shizong oversaw a refinement of his grandfather's dual system of government, which brought the structure of the Southern Administration closer to the model used by the Tang dynasty. Emperor Shizong would be succeeded by Emperor Taizong's son Yelü Jing, also known as Emperor Muzong of Liao. Emperor Muzong, who died in 969, would be the second and the last of the emperors to succeed Abaoji who was not a direct descendant of Yelü Bei.
