Want to Understand Asian Geopolitics? Go Back to Genghis Khan

July 5, 2021 Topic: Security Region: Asia Blog Brand: The Reboot Tags: MongoliaAsiaChinaConquestAsymmetric Warfare

Want to Understand Asian Geopolitics? Go Back to Genghis Khan

The Mongols began besieging the more than one million residents of Beijing.

A Five-Year Siege

In 1265, a Chinese allied naval force destroyed 100 Song ships in a river battle, and Mongol troops defeated the isolated Song army to regain control of part of Sichuan. The key to conquering the Song was capturing the twin fortress cities of Xiangyang and Fancheng. Both cities had thick walls with wide moats protecting the convergence of the Han and Yellow Rivers. In 1268, the Mongols built fortifications downriver from Xiangyang on the Han River to cut off resupply of the city by ship. Most Song ships were able to run by the Mongol forts and resupply Xiangyang and Fancheng. Chinese ships allied with the Mongols were brought in to block the passage between the Mongol forts. More than 20 miles of siege lines were built around Xiangyang and Fancheng on both sides of the Han River.

The Mongols and their Chinese engineers set up trebuchets and began firing incendiary clay bombs and exploding biochemical projectiles they had learned from the Jin at the siege of Beijing in 1215. The Song fired incendiary bombs and biochemical projectiles at the Mongols as well, causing great destruction and loss of life on both sides. The Mongols had to pull back after their wooden siege walls and trebuchets caught fire from the bombardments, leaving the Mongols with no cover, while the Song defenders took shelter behind the twin cities’ stout rock and masonry walls.

In 1269, Kublai Khan sent another 20,000 troops to replace those in the previous year’s fighting. More than 3,000 Song ships attacked the Mongol forts on the Han River in an effort to break the blockade, but 500 ships were sunk by Kublai Khan’s brilliant admiral Liu Cheng, who had defected to the Mongols. Mongol and Chinese troops clambered aboard the Song vessels and beheaded hundreds of Song soldiers and sailors.

The besieged Song tried several unsuccessful attempts to break out but were defeated each time with thousands of casualties. In 1271, 100 Song ships successfully broke through a boom across the Han River to bring 3,000 soldiers and much-needed supplies to reinforce Xiangyang. The siege dragged on with no real advantage for either side until Kublai Khan decided to send a Muslim engineer captured during the siege of Baghdad to China to build a giant 40-ton trebuchet that could hurl 220-pound projectiles more than 600 feet to breach the cities’ walls. After a few days, a breach was opened and Mongol troops stormed through to meet the Chinese defenders. For days, men fought and died in the vicious battle at the breach.

The Song were able to throw more soldiers into Fancheng to defend the breach from a pontoon bridge that connected Xiangyang across the Han River. The Mongols called off the assault on the breach and used their giant trebuchet to widen the breach and destroy the pontoon bridge. Incendiary bombs fired from the trebuchet struck the bridge and consumed it. With Fancheng cut off from reinforcements, the Mongols assaulted the widened breach. The disheartened defenders held on for several hours before resistance broke and the Mongols poured into the city and began massacring the inhabitants. The Mongols took the last 3,000 Song soldiers and 7,000 inhabitants to the walls facing Xiangyang and in full view slit the prisoners’ throats and threw them off the wall.

The Mongols then dismantled their giant trebuchet and repositioned it across the river facing Xiangyang. The first shot from the trebuchet forced a tower to collapse in a great crash as the Song inhabitants screamed in terror. Kublai Khan offered to spare the inhabitants and to reward the Song commander if he would surrender the city. Xiangyang was surrendered and the Song heartland was open to the Mongols. The siege had lasted from 1268 to 1273.

74 Years of Conquest

In 1274, the Mongols headed down the Han River, bypassing Song fortresses and emerging onto the flood plains of the Yangtze River. The Mongols now faced the impregnable fortress of Yang-lo. The Mongols sacrificed several thousand Chinese troops on a frontal attack on Yang-lo while most of the Mongol army, carrying a number of ships, bypassed the fort and crossed the river upstream. Then the Mongol and Chinese fleet came down the Yangtze and attacked the Song fleet from both front and behind. The Song boats were packed so close together on the river that incendiary bombs fired from Mongol catapults set much of the Song fleet on fire. Thousands perished in the flames. Fortress Yang-lo and the 100,000 cut-off Song troops surrendered the next day.

In 1275, Jia Sidao set out from the capital of Hangzhou at the head of 100,000 Song troops and another fleet of 2,500 ships in a last-ditch effort to stop the Mongol juggernaut. A massive cavalry and infantry battle took place on both sides of the river. The Mongols and their Chinese allies pushed back the Song army and boarded their ships from both ends of the river, beheading thousands of Song troops and capturing 2,000 ships. It was another overwhelming victory for the Mongols. Jia Sidao was later assassinated by a Song officer.

The city of Hangzhou refused an offer to surrender peacefully and was burned. As usual, the Mongols massacred the city’s inhabitants. On February 21, 1276, the boy emperor Zhao Xian came out of Hangzhou, bowed toward the north in obeisance to Kublai Khan, and turned over the capital and the rest of the Song Empire to the Mongols. The Mongol conquest of China had taken 74 years and claimed the lives of as many as 25 million Chinese from war, plague, and famine.

The ramifications of the Mongol conquest of China were felt for some time. The Ming, who overthrew the Mongols in 1368, became obsessed with improving and lengthening the Great Wall to close to 5,000 miles (including walls that backed up walls) to prevent another Mongol invasion of China. The Great Wall as it existed from the time of the Ming Dynasty was an expensive reaction to the Mongol conquest of China. In the end, the improved Great Wall did not save China. In 1644, a Mongol-like nation, the Manchu, conquered China and ruled the unhappy nation until 1911.

Originally Published in 2018.

This article by Steven M. Johnson originally appeared on the Warfare History Network.

Image: Flickr.