After Kaifeng's fall to Liao, Shi Chonggui and his family (including Shi Jingtang's wife Empress Dowager Li) were put under house arrest by the Liao general (formerly a subordinate of Du Wei's), Zhang Yanze, whom Emperor Taizong sent as forward commander to take control of the city.
Meanwhile, Zhao, finally realizing that Emperor Taizong had no intent on fulfilling his promise to make Zhao emperor of China, had Li Song request, on his behalf, for him to be made crown prince.