Briefly, at the end of the Second World War in 1945, Japan returned territories that had been captured from China. One of these was an island that the Japanese called Formosa and the Chinese called Taiwan. At that time, China had been fighting a civil war for nearly twenty years, between the Communists led by Mao Tse-tung and the Nationalists led by Chiang Kai-shek. Mao got the upper hand, and Chiang was forced to take refuge on the island of Taiwan. China did not recognise Taiwan as a separate country, known as Nationalist China and for many years the two were technically still involved in their civil war, although not much real fighting took place. Mainland China can claim to be a superpower, but Taiwan is not one, unless on economic grounds. It was successful as the source of many cheap imports to the west until Communist China recently began to expand its own economy.