Zhangjiakou was historically known to the Europeans as Kalgan until the mid 20th century. In August 1211, there raised the Badger's Mount Campaign, Genghis Khan 90,000 strong force destroyed the 450,000 strong Jin Dynasty army. In 1937 the Japanese occupied the region and made Kalgan the capital of the autonomous Cha-nan (South Chahar) Province. The Federated Mengjiang Commission was set up to supervise the economic affairs, banking, communications, and industry of Japanese-occupied Inner Mongolia (Mengjiang).