The Chinese Civil War was a civil war fought from 1927 to 1951, because of a difference in thinking between the Chinese Communist Party (CCP) and the Nationalist Kuomintang (KMT). The war was a fight for legitimacy as the government of China. The war began in April 1927, because of the 'Northern Expedition" (國民革命軍北伐) and mostly ended in 1950. Some people say the war has not ended, but no large battles have started since that year. The relations between the Republic of China (ROC) and the People's Republic of China (PRC) are bad because both still say they are the legitimate sovereign government of all of China. The Chinese Civil War was the third largest war in all of time after World War II and World War I.