During World War II, China was divided into three occupation zones among the Communist (CCP) forces led by Mao Tse-tung based in the north, the Nationalist (Kuomintang, KMT) forces led by Chiang Kai-shek based in the west, and the Japanese armed forces along the eastern seaboard. When the U.S. enters World War II on December 8, 1941, the United States becomes an ally of China.