In AD 696, the Khitan rose against Chinese hegemony under the leadership of Li Jinzhong and his brother-in-law Sun Wanrong. At the time, Li Kaigu was a general under Li Jinzhong. By AD 697, Li Jinzhong had died, and Sun had been defeated and killed. Li Kaigu and fellow Khitan general Luo Wuzheng (駱務整) surrendered to Wu Zetian's Zhou Dynasty. Initially, Zhou generals wanted to put Li Kaigu and Luo to death in retaliation for their victories over Zhou forces, but the chancellor Di Renjie intervened and persuaded Wu Zetian to instead make them her generals.
Li Kaigu was subsequently able to suppress the remaining Khitan forces. In AD 700, Li Kaigu was named the Duke of Yan and subsequently given the surname of "Wu." (Presumably, he changed his surname back to Li after Wu Zetian's son Emperor Zhongzong of the Tang Dynasty returned to the throne in AD 705 after a coup and restored the Dynasty.) However, he was unable to defeat Dae Jo-yeong, who eventually established the kingdom of Balhae. It is not known when Li Kaigu died.
Battle of Tianmenling
The Battle of the Astronomical Battle or the Battle of the Tianmun Ling took place in AD 698 between the Gaoqing Daojongong and the Tang Dynasty.
After the destruction of Goguryeo by Silla and the coalition forces of the party, Dae Joo - young went to the lord of the party with his father. In May, AD 696, when Lee Jing-chong and Son-Man-榮ong of Rebellion revolted in the Tang dynasty, they were caught up in confusion. Then, in spite of the emancipation policy of Huan Teng Wu, Goguryeo created a force in the east.
The Tang Dynasty sent out an armed force and fought. Dae Joo-young, who defeated them by rallying gunwagi, a group of people from the Malgalese and Goguryeo. Dae Jo Young defeated the Tang army in the royal court and laid the foundations for establishing the Bohai Sea. In AD 698, Daejo-yong built the pavilion under the Dongmoo-san in Jilin castle today.