The Jingkang Incident-Sequel І
Towards the end of the Northern Song Dynasty, in the state of Liao in northern China, under the rule of King Tianzuo (r. 1101-1121), the Nuzhen people (later called Manchu) in the northeast were cruelly oppressed and exploited, and yearned to cast off the yoke of the Liao. Aguda, taking advantage of his people's sentiments against oppression, in the process of attacking Liao, established the state of Jin, and after its founding continued to lead his troops against Liao.
In 1120 Song and Jin signed the "Agreement over the Sea," which meant the two countries simultaneously launched an attack upon Liao. After conquering the Liao, the land south of the Great Wall was to fall under the jurisdiction of the Song, while the Jin would be entitled to the Annual Monetary Tributes, which used to be the Liao's privilege. In reality, the agreement maintained the humiliation of the Northern Song. However, the Song Emperor Huizong approved it readily and did not guard himself against the Jin.
In 1122, only after seeing the Jin troops score a series of victories in their attacks upon the Liao, did the Song court send Tong Guan and Cai You to command 100,000 troops, to march towards the capital of Liao, only to be badly defeated. The Liao troops were no match for the Jin, but this time they encountered a rival whose combativeness was even weaker. Before long, the Song deployed 200,000 troops for another invasion of Liao, but again suffered a crushing defeat. To cover up his incompetence and the defeats, Tong Guan conspired with the Jin to launch an attack on Yanjing, which was just what the Jin rulers wanted. For they had long harbored a plan to cross over the Great Wall, and seize more land. The Jin troops promptly drove towards Yanjing in three directions, and achieved this goal without hitch.
In 1125 the Jin King Taizong, after conquering the Liao, assembled his troops, and then drove south into the Northern Song. They advanced in two directions, seizing cities and military strongholds, crossing over the Yellow River successively, and pushing close to the capital (today's Kaifeng, Henan Province).
Previously, the Jin troops had once tried to fight their way into the capital. At that time, Song Emperor Huizong had fled south in panic, and conceded the throne to the Crown Prince, Emperor Qinzong. Faced with the initial attack of the Jin troops, the Song court managed to strike a deal by pleading for a humiliating peace. Once again the Song Emperor Qinzong still adhered to his old strategy of capitulation, and tried to plead for peace, rather than launch military preparations. This was conducive to the Jin's military strategy.