The first 25 years at the beginning of the 12^th century saw the darkest age ruled by the fatuous and self-indulgent Emperor Huizong. Although Huizong usefully kept down the two large-scale peasant uprisings, his dynasty was doomed with the rising Nuzhen tribe.

There lived in the Changbai Mountains and the Helongjiang Valley the ancestors of the Nuzhen people long before. The name "Nuzhen" did not appear in historical records until the Five Dynasties Period (907- 960) when it was under the control of the Khitan. In 1115, the great headman of the Nu zhen tribe Yelu Abaoji established a new dynasty -- the Jin Dynasty in 1115 and proclaimed himself emperor. Historically, Yelu Abaoji was called as Emperor Taizu. In 1125, the emperor of Liao surrendered to Jin and the state of Liao came to its end. Then Jin started to invade Northern Song. In 1127, Emperors Huizong and Qinzong were deposed, ending the Northern Song Dynasty (960-1127). This event was referred to as Catastrophe of Jingkang in the history.

In the same year, Zhao Gou, the younger brother of Song Emperor Qinzong, ascended the throne in Yingtianfu (today's Nanjing) after the withdrawal of the Jin troops, and later moved the capital to Lin'an (western Hangzhou City of Zhejiang Province). Zhao Gou still called his regime the "Great Song", which became known as the Southern Song, and chose the reign title of Jianyan.