 By summer 880, however, the tide began to change against Li Keyong and his Shatuo forces.As the newly Tang-commissioned military governor of Datong, Li Zhuo (李涿), was joining forces with Li Keju the military governor of Lulong Circuit (盧龍, headquartered in modern Beijing) and the Tuyuhun chieftain Helian Duo against Li Keyong, Li Keyong left his officer Gao Wenji (高文集) in charge of his base at Shuo Prefecture (朔州, in modern Shuozhou, Shanxi) and stationed himself at Xiongwu Base (雄武軍, in modern Chengde, Hebei) to defend against Li Keju.Li Zhuo used this opportunity to entice Gao to surrender.