History of The Song Dynasty - Defeat of Jin Invasion, 1161

Defeat of Jin Invasion, 1161

In 1153 the Jin Emperor Hailingwang, born as Wányán Liàng (完顏亮), moved the empire's capital from Huining Fu in northern Manchuria (south of present-day Harbin) to Zhongdu (now Beijing). Four years later in 1157 he razed Beijing, including the nobles’ residences, and moved the Jin's southern capital from Beijing to Kaifeng. It was here at the former seat of the Song Dynasty that he began a large project of reconstruction (since the siege against it in 1127). For much of his reign there was peace between Jin and Song, while both states upheld an uninterrupted flow of commercial trade between each other. While amassing tribute from the Southern Song, the Jin Dynasty also imported large amounts of tea, rice, sugar, and books from the Southern Song. However, Hailingwang reopened the Jin Dynasty's armed conflict with the Song by the 1160s.

Emperor Wanyan Liang established a military campaign against the Southern Song in 1161, with 70,000 naval troops aboard 600 warships facing a smaller Song fleet of only 120 warships and 3,000 men. At the Battle of Tangdao and the Battle of Caishi along the Yangtze River, Jin forces were defeated by the Southern Song navy. In these battles, the Jin navy was wiped out by the much smaller Song fleet because of their use of fast paddle-wheel crafts and gunpowder bombs launched from trebuchet catapults (since explosive grenades and bombs had been known in China since the 10th century). Meanwhile, two simultaneous rebellions of Jurchen nobles, led by soon-to-be crowned Jin Emperor Wányán Yōng (完顏雍) and Khitan tribesman, erupted in Manchuria. This forced the reluctant court of the Jin Dynasty to withdraw its troops from southern China to quell these uprisings. In the end, Emperor Wányán Liàng failed in taking the Southern Song and was assassinated by his own generals in December 1161. The Khitan uprising was not suppressed until 1164, while the Treaty of Longxing (隆興和議) was signed in 1165 between Song and Jin, reestablishing the 1142 border line and ushering in four decades of peace between the two.

In the years 1205 and 1209 the Jin state was under raid attacks by Mongols from the north, and in 1211 the major campaign led by Genghis Khan was launched. His army consisted of fifty thousand bowmen, while his three sons led armies of similar size. Patricia Ebrey writes that at this point the Mongol population could not have been greater than 1.5 million, yet they boosted their numbers by employing Khitans and Han Chinese "who felt no great loyalty to their Jurchen lords." After a Jurchen general murdered Emperor Weishaowang of Jin in 1213 and placed Emperor Xuanzong of Jin on the throne, a peace settlement was negotiated between Jin and the Mongol forces in 1214, as Genghis made the Jin Dynasty a vassal state of the Mongol Empire. However, when the Jin court moved from Beijing to Kaifeng, Genghis saw this move as a revolt, and moved upon the old Jin capital at Beijing in 1215, sacking and burning it. Although the now small Jin state attempted to defend against the Mongols and even fought battles with the Song in 1216 and 1223, the Jin were attacked by the Mongols again in 1229 with the ascension of Ögedei Khan. According to the account of 1232, written by the Jin commander Chizhan Hexi, the Jurchens led a valiant effort against the Mongols, whom they frightened and demoralized in the siege of the capital by the use of 'thunder-crash-bombs' and fire lance flamethrowers. However, the capital at Kaifeng was captured by siege in 1233, and by 1234 the Jin Dynasty finally fell in defeat to the Mongols.

The Western Xia Dynasty met a similar fate, becoming an unreliable vassal to the Mongols by seeking to secure alliances with Jin and Song. Genghis Khan had died in 1227 during the 5 month siege of their capital city, and being held somewhat responsible for this, the last Xia ruler was hacked to death when he was persuaded to exit the gates of his city with a small entourage.