居庸関
In the spring of 1122, the Liao court rallied around Prince Yelü Chun in Nanjing, and defeated two Song army advances. After Yelü Chun died of illness in the early summer, Guo Yaoshi, an ethnic Han commander in the Liao Army, defected to the Song and led the vanguard of the Song Army in a raid on Nanjing. The raiders entered the city, but the Liao Empress Xiao continued to resist from the walled palace complex. After three days of street fighting, Liao reinforcements reached the city ahead of the main Song Army, and managed to expel Guo Yaoshi's forces. In the winter of 1122, the Jin Army drove through the Juyong Pass and marched on Nanjing from the north. This time, Empress Xiao fled to the steppes and the remaining Liao officials capitulated. Wanyan Aguda allowed the surrendering officials to retain their positions and encouraged refugees to return to the city, which was renamed Yanjing.