Mongol–Jin War: The Mongols entered and began looting Kaifeng, the capital of the Jin dynasty of China, after a 13-month siege.

The Mongol conquest of the Jin dynasty, also known as the Mongol–Jin War, was fought between the Mongol Empire and the Jurchen-led Jin dynasty in Manchuria and North China. The war, which started in 1211, lasted over 23 years and ended with the complete conquest of the Jin dynasty by the Mongols in 1234.

The Mongol Empire was the largest contiguous empire in history. Originating in present-day Mongolia in East Asia, the empire at its height stretched from the Sea of Japan to Eastern Europe, extending northward into the Arctic; east and southward into the Indian subcontinent, mounting invasions of Southeast Asia, and conquering the Iranian plateau; and reaching westward as far as the Levant and the Carpathian Mountains.

Kaifeng is a prefecture-level city in east-central Henan province, China. It is one of the Eight Ancient Capitals of China, having been the capital eight times in history, and is most known for having been the Chinese capital during the Northern Song dynasty.

The Jin dynasty, officially known as the Great Jin, was a Jurchen-led imperial dynasty of China and empire ruled by the Wanyan clan that existed between 1115 and 1234. It is also often called the Jurchen dynasty or the Jurchen Jin after the ruling Jurchen people. At its peak, the empire extended from Outer Manchuria in the north to the Qinling–Huaihe Line in the south.

In the siege of Kaifeng from 1232 to 1233, the Mongol Empire captured Kaifeng, the capital of the Jurchen-led Jin dynasty. The Mongol Empire and the Jin dynasty had been at war for nearly two decades, beginning in 1211 after the Jin dynasty refused the Mongol offer to submit as a vassal. Ögedei Khan sent two armies to besiege Kaifeng, one led by himself, and the other by his brother Tolui. Command of the forces, once they converged into a single army, was given to Subutai who led the siege. The Mongols arrived at the walls of Kaifeng on April 8, 1232.