Mao was the son of a prosperous peasant in Shaoshan, Hunan. He supported Chinese nationalism and had an anti-imperialist outlook early in his life, and was particularly influenced by the events of the Xinhai Revolution of 1911 and the May Fourth Movement of 1919. He later adopted Marxism–Leninism while working at Peking University as a librarian. He became a founding member of the Chinese Communist Party (CCP), leading the Autumn Harvest Uprising in 1927. During the Chinese Civil War between the Kuomintang (KMT) and the CCP, Mao helped to found the Chinese Red Army, led the Jiangxi Soviet's radical land reform policies, and ultimately became head of the CCP during the Long March. Although the CCP temporarily allied with the KMT under the Second United Front during the Second Sino-Japanese War (1937–1945), China's civil war resumed after Japan's surrender. Mao's forces defeated the Nationalist government, which withdrew to Taiwan in 1949.