Siege of Diaoyu Castle

The Mongol Siege of Diaoyu Castle was a battle between Song dynasty China and Mongol empire in the year of 1259.Möngke Khan, the fourth khan of Mongol empire lost his life in this battle making it the only battle where Mongols lost their khan during their conquest of the world. This battle was preceded by the siege of Baghdad in the year of 1258. In a world-wide warfare, the siege of Diaoyu castle can be seen as a major setback of the Mongol conquest.

The Mongol Empire under Genghis Khan conquered vast lands and subjugated nations. Genghis Khan's last battle was fought in Western Xia but his life had come to an end before he was able to conquer it. His successors carried on his ambition. In the year of 1234, the Mongols conquered the Jurchen empire with the assistance of the Song dynasty.

In the same year, Song China attempted to take back its northern territories originally occupied by the Jurchens. In September 1234, the Mongols responded with the siege of Luoyang. The Song army holding Luoyang was short of food supplies. Additionally, the Mongols led the water of Yellow River into the city causing great casualties among the Song army.

The fall of Luoyang was simply a prologue of a series of upcoming battles which lasted decades. The Mongols blamed the Song for "breaking the alliance". However, it was more of an excuse for further Mongol expeditions.

After 1234, the Mongols launched an all-out war against the Song dynasty. They attacked from both the east and west flanks, crippling the Chinese defenses. Despite these initial military successes, the Song army managed to retaliate. No significant advancement was made.

Under the command of Meng Gong, Yu Jie and other generals, the Song army fended off the advancing Mongols. In Sichuan, Meng Gong led the Song army as it held its position against the Mongols in 1239 and 1240.

In the year of 1243, Yu Jie was appointed the commander of the Song army in Sichuan. When he actually came to Sichuan, he discovered the fact that, due to the Mongol invasion, the Sichuan region was in a state of anarchy. The Song army was able to defend themselves by forming smaller military units that does not have superiority over each other. In order to reverse the dire situation in Sichuan, Yu sought the advice of the people under his command. Ran Lian and Ran Pu, two hermits of Bozhou came to his office and offered him the plan of building a castle in Hechuan. Specifically, the plan was to build a castle on Diaoyu mountain of Hechuan. Hechuan sits at the eastern entrance of Sichuan region, the Mongols had to pass it before advancing further into the interior of Sichuan. Thus, the Diaoyu mountain was a great vantage point for the defensive of the Song army.

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