In the Second World War, the Japanese Army invaded and occupied Malaya, North Borneo, Sarawak, and Singapore for over three years. During this time, ethnic tensions were raised and nationalism grew. Popular support for independence increased after Malaya was reconquered by Allied forces. Post-war British plans to unite the administration of Malaya under a single crown colony called the "Malayan Union" met with strong opposition from the Malays, who opposed the weakening of the Malay rulers and the granting of citizenship to the ethnic Chinese. The Malayan Union, established in 1946, and consisting of all the British possessions in the Malay Peninsula with the exception of Singapore, was quickly dissolved and replaced on 1 February 1948 by the Federation of Malaya, which restored the autonomy of the rulers of the Malay states under British protection.