Although the Chinese contribution to Allied victory in World War II (1939-1945) is often ignored, China fought the Japanese Empire for far longer than any other belligerent nation. By the time that the Sino-Japanese War became absorbed into the wider conflict at the end of 1941, Chinese armies had already suffered huge casualties and half the country had been lost. By fighting on with Allied support, China tied down a million Japanese troops. After Japan's defeat in 1945, China was immediately plunged back into civil war between Chiang Kai-shek's Nationalists and Mao Tse-tung's Communists; and the latter's victory in 1949 changed the world for the rest of the 20th century and beyond.