In the first year of Qianning of the Tang Dynasty (894), King Jin and Hedong Jiedu made Li Keyong capture Youzhou (now Beijing). In order to maintain his influence in Youzhou, Li Ke used Liu Rengong to leave Lu Longliu as the queen, and soon after, the Tang court officially appointed Liu Rengong as the envoy of Lu Longjie, recognizing Liu Rengong's jurisdiction over Youzhou. Liu Rengong also began to occupy Yan land alone and established a separatist regime. It stands to reason that Liu Rengong's success is due to Li Keyong, and he should have been loyal to Li Keyong, but Liu Rengong is purely a "white-eyed wolf", and after Liu Rengong gained a firm foothold in Youzhou, he began to ignore Li Keyong's instructions.
In the fourth year of Qianning (897), Tang Zhaozong was held hostage in Huazhou by Han Jian, after Li Keyong heard the news, he actively prepared the soldiers and horses to escort the king, and asked Liu Rengong for reinforcements, Liu Rengong did not give face at all, Li Keyong was furious, so he led the army to conquer Youzhou, but he was defeated, and Liu Rengong also took this opportunity to completely get rid of Li Keyong's control and became the undisputed king of Youzhou. Li Keyong lost face after this defeat, and Youzhou also became a knot in Li Keyong's life (Li Keyong also specially instructed his son Li Cunqiao to solve Liu Rengong's evil anger for himself before he died). After that, Liu Rengong took Youzhou as a base, went on expeditions, and at its peak had 300,000 troops, expanding 2,000 miles, occupying present-day Beijing and northern Hebei and parts of eastern Liaodong, becoming a force to be reckoned with in the north.
Soon after, Liu Rengong proclaimed himself the king of Yan, and built a palace on Da'an Mountain in Youzhou, which was magnificent, and the beautiful women lived in it. In order to satisfy his own selfish desires, coupled with the officials and huge army in Youzhou, Liu Rengong did his best to exploit the people in the jurisdiction, causing a large number of people in Youzhou to flee, many of whom fled to the Khitan, which brought huge strength to the Khitan who lacked labor and advanced production technology, making the Khitan stand out in the battle for grassland hegemony and gradually unify the grassland.
"At the beginning of the Tang Dynasty, the feudal towns were arrogant, annexing each other's neighboring domains, and many Yan soldiers died and returned to the Khitan, and the Khitan became stronger and stronger. ”
In the first year of Kaiping of Later Liang (907), Liu Shouguang, the second son of Liu Rengong, staged a coup d'état, arrested and imprisoned Liu Rengong. and defeated Liu Shouwen, the eldest son of Liu Rengong (the legal heir), in Lutai (located in today's Tianjin), and completely controlled the military and political power of Youzhou. Liu Shouguang was more brutal than Liu Rengong, and the Yandi soldiers fled one after another to avoid disaster, and Youzhou was declining. In August of the first year of Qianhua (911), Liu Shouguang proclaimed himself the Emperor of Dayan and established the Dayan regime. In the second year of Qianhua (912), Li Cunmiao took Zhou Dewei, the general of Hedong, as the commander, commanded 30,000 He Dong troops, and combined the soldiers and horses of the two towns to attack Liu Shouguang, which opened the prelude to the demise of the Jiyan regime.
Because of the brutal rule of Liu Rengong and Liu Shouguang's father and son in Youzhou, which led to the loss of the hearts of the people in Yandi, after the Hedong Army entered Yandi from Qigou Pass, the prefectures of Shan, Zhuo, Wu and Shun all heard the wind and surrendered, and the Hedong Army advanced to the city of Youzhou almost without blood. Immediately, the Hedong Army besieged Youzhou City, and after more than a year of siege, Liu Shouguang was forced to open the city and surrender to the Hedong Army. The Hedong army captured more than 300 members of Liu Rengong's family, as well as Liu Shouguang and Liu Shouguang's wives Li and Zhu, and their sons Liu Jixun, Liu Jifang, and Liu Jizuo. So far, Li Cunmiao has won the entire territory of Youzhou, and Youzhou's people, land, soldiers, and taxes have greatly enriched Li Cunmiao's strength, and injected fresh blood into Li Cunmiao's struggle for hegemony with the Later Liang Dynasty. After that, Li Cunqiao tied Liu Rengong and Liu Shouguang father and son together and sacrificed prisoners at the Taimiao of the Jin Kingdom in Jinyang (now Taiyuan). After the prisoner gift, Li Cunqiao sent his fierce general Li Cunba to escort Liu Shouguang's father Liu Rengong to Yanmen, break his stomach and take his heart to pay tribute to the former king Li Keyong, and then beheaded Liu Shouguang, realizing Li Keyong's last words.
During the battle of Li Cunmiao's annihilation of Yan, a large number of Yandi soldiers and civilians fled to the Khitan, making the Khitan "both the people of Yanzhong and the grammar taught, and gradually prospered", and the road to the rise of the Khitan became more and more smooth, and gradually moved from a supporting role in history to the center stage of history.