장각
According to the "Twenty-Four Histories", in 1123, three years after the fall of Liao, a Jin general Zhang Jue (), defected to the Song dynasty. Since he was governor of the Jin-controlled Pingzhou Prefecture, an area just north of the Sixteen Prefectures on the other side of the Great Wall, Pingzhou Prefecture was also merged into Song territory. The Song imperial court initially welcomed the defection and awarded Zhang Jue an honorific title and land. The Jin dynasty, on the other hand, sent a small army aimed to overturn the defection but was defeated by Zhang Jue's troops.