The Jingkang Incident
The Jingkang Incident, named after Qinzong's era, is the name given to the Jin conquest of the Song capital, Bianjing (modern Kaifeng), during the Jin–Song wars of 1125 to 1127.
The First Siege of Bianjing
The Jin attacked in two armies. The western army besieged Taiyuan in Shanxi, while the eastern army swept south from the Yan region around modern Beijing, crossed the Yellow River early in 1126 and laid siege to Bianjing.
Qinzong gave command of the city's defence to the minister Li Gang, who held the walls. But the emperor wavered between resistance and negotiation, and he dismissed Li Gang in the hope of peace, recalling him only after protests in the capital.
The siege was lifted when the Song agreed to a huge indemnity in gold, silver and silk and promised to cede three strategic prefectures in the north: Taiyuan, Zhongshan and Hejian.
The Second Siege
Once the Jin armies had withdrawn, the court relaxed and Huizong returned to the capital. Some generals urged that strong forces be kept on the Yellow River, but the advice was not followed.
The Song failed to hand over the promised prefectures, and in the autumn of 1126 the Jin invaded again. Taiyuan fell after a long siege, the two Jin armies crossed the Yellow River and advanced on Bianjing, and the cities in their path gave little resistance.
The capital fell in January 1127. In the spring the Jin carried off Qinzong, his father Huizong, the empresses, thousands of members of the imperial clan and many officials of the court, together with the palace treasures and the imperial library.
One of Huizong's sons, Zhao Gou, escaped capture. He was proclaimed emperor later in 1127 and, as Emperor Gaozong, founded the Southern Song.