Liao (9 16 ~ 1 125) was a considerable political power established by the Qidan nationality in northern China. It started at the same time as the Five Dynasties and ended almost at the same time as the Northern Song Dynasty. As the rule of ethnic minorities, although they fought against the Central Plains all the year round, they were deeply influenced by the Han culture in the Central Plains politically, economically and culturally.

Lu Ye Abaoji, the founding emperor of the Khitan, was originally the military leader of the tribal alliance. With its strong military strength, it defeated Lage, Diela and others, became emperor in 9 16 A.D., and established the Qidan State (Qidan was renamed Liao in 938, Qidan in 983, and Liao in 1066). After the founding of the Khitan, Bao Zheng gradually wiped out the weak tribes all over the country, and in 926 AD, he wiped out the Bohai Kingdom (now eastern Liaoning to southern Heilongjiang), basically completing his journey of reunification.

From 926 to 947 AD, it was the reign of Emperor Taizong Ye Ludeguang. At that stage, Liao got sixteen states from Shi Jingtang. On this basis, Liao began to expand to the Central Plains. Ye Ludeguang marched into the State of Jin several times, hoping to conquer the whole of China, but his plan ran aground due to the resistance of the Central Plains people.

After Emperor Taizong, after two generations of Sejong Ruan (947~950) and Mu (95 1~969), fierce disputes took place within Liao's rule, and it was not until Jing Zong Xian (969~982) that it gradually stabilized.

After Jing Zong's death, his 12-year-old son, Lu Ye Longxu, acceded to the throne and became the Emperor of Emperor Sheng Zong of Liao Dynasty. Because Sanzong was still young, she was regent by her mother Xiao Taihou. Xiao Taihou was a famous female politician in the history of Liao Dynasty. She appointed Yelvxiuge as the general, invaded the Song Dynasty in the fourth year of Shengzongtong (987) and defeated Song Jun. After that, Liao sent troops to attack the Song Dynasty for years. In the twenty-second year of Shengzong, Enemy at the Gates, Liao, signed the "Union of Yuan Tan" with him, forcing the Song Dynasty to pay tribute to Liao every year. Since then, the two countries have settled down relatively. Emperor Shengzong of Liao relied on the tribute of Song State to develop the economy of Liao State, which reached its peak in history.

After the prosperous period of Emperor Shengzong and Emperor Xingzong (103 1~ 1055), Liao began to decline. In A.D.11kloc-0/year, Emperor Zuo of Liao Tian ascended the throne. At this time, with the rise of Jurchen nationality, the rule of Liao country was gradually threatened. In A.D.115, the Jin army captured Huanglongfu, an important town in Liao country, and later entered into a "maritime alliance" with the Song Dynasty to jointly resist the gold. In a few years, Jin Bing occupied most of the land in Liao country, including Liaoyang Prefecture in Tokyo. In 1 125, the state of Jin captured the fugitive emperor Tianzuo, and the state of Liao died.