The Empire of Japan's Kwantung Army invaded the Manchuria region of the Republic of China on 18 September 1931, immediately following the Mukden incident. At the war's end in February 1932, the Japanese established the puppet state of Manchukuo. Their occupation lasted until the success of the Soviet Union and Mongolia with the Manchurian Strategic Offensive Operation in mid-August 1945, towards the end of the Second World War.

The Kwantung Army was a general army of the Imperial Japanese Army from 1919 to 1945.