<P> The Japanese invasion of Manchuria began on 18 September 1931, when the Kwantung Army of the Empire of Japan invaded Manchuria immediately following the Mukden Incident . The Japanese established the puppet state of Manchukuo, and their occupation lasted until Soviet Union and Mongolia launched the Manchurian Strategic Offensive Operation in 1945 . </P> <P> The Chinese--Japanese dispute in July 1931 (the Wanpaoshan Incident) was followed by the Mukden Incident, on 18 September 1931 . The same day as the Mukden Incident, the Japanese Imperial General Headquarters, which had decided upon a policy of localizing the incident, communicated its decision to the Kwantung Army command . However, Kwantung Army commander - in - chief General Shigeru Honjō instead ordered his forces to proceed to expand operations all along the South Manchuria Railway . Under orders from Lieutenant General Jirō Tamon, troops of the 2nd Division moved up the rail line and captured virtually every city along its 730 - mile length in a matter of days, occupying Anshan, Haicheng, Kaiyuan, Tiehling, Fushun, Szeping - chieh, Changchun, Kuanchengtzu, Yingkou, Antung, and Penhsihu . </P> <P> Likewise on 19 September, in response to General Honjō's request, the Joseon army in Korea under General Senjūrō Hayashi ordered the 20th Infantry Division to split its force, forming the 39th Mixed Brigade, which departed on that day for Manchuria without authorization from the Emperor . </P> <P> Between 20 September and 25 September, Japanese forces took Hsiungyueh, Changtu, Liaoyang, Tungliao, Tiaonan, Kirin, Chiaoho, Huangkutun and Hsin - min . This effectively secured control of Liaoning and Kirin provinces and the main line of rail communications to Korea . </P>

Who held manchuria and why did japan want it