The island of Taiwan, formerly known as Formosa, was inhabited by aborigines before the 17th century, when Dutch and Spanish colonies opened the island to mass Han immigration. After a brief rule by the Kingdom of Tungning, the island was annexed by the Qing dynasty, the last dynasty of China. The Qing ceded Taiwan to Japan in 1895 after the Sino-Japanese War. While Taiwan was under Japanese rule, the Republic of China (ROC) was established on the mainland in 1912 after the fall of the Qing dynasty. Following the Japanese surrender to the Allies in 1945, Republic of China took control of Taiwan. However, the resumption of the Chinese Civil War led to the Republic of China's loss of the mainland to the Communists, and the flight of the Republic of China government to Taiwan in 1949. Although the ROC continued to claim to be the legitimate government of China, its effective jurisdiction had, since the loss of Hainan in 1950, been limited to Taiwan and its surrounding islands, with the main island making up 99% of its de facto territory. As a founding member of the United Nations, Republic of China continued to represent China at the United Nations until 1971, when the PRC assumed China's seat, causing the ROC to lose its UN membership.