 However, the Soviet occupation of Manchuria was long enough to allow the Communist forces to move in en masse and arm themselves with the military hardware surrendered by the Imperial Japanese Army, quickly establish control in the countryside and move into position to encircle the Nationalist government army in major cities of northeast China.Following that, the Chinese Civil War broke out between the Nationalists and Communists, which concluded with the Communist victory in mainland China and the retreat of the Nationalists to Taiwan in 1949.The question as to which political group directed the Chinese war effort and exerted most of the effort to resist the Japanese remains a controversial issue.