The ROC government participated in the 1943 Moscow Conference, the Dumbarton Oaks Conference, and the United Nations Conference on International Organization and was a charter member of the United Nations after participating in the alliance that won World War II. In 1949, the Nationalists lost the Chinese Civil War in mainland China and retreated to Taiwan, Penghu, Kinmen and Matsu, forming a rump state. Despite the major loss of territory, the ROC continued to be recognized as the legitimate government of China by the UN and by many non-Communist states.