The Dutch authorities, after various changes to the administration of the eastern islands of the East Indies, established the Great East region in 1938. Four years later, the Japanese invaded, and this area was placed under the control of the Imperial Japanese Navy. Following the Japanese surrender and the Indonesian declaration of independence in August 1945, Indonesian republicans began fighting to secure Indonesian independence from Dutch colonial control. However, Dutch administrators backed by Australian troops arrived in the area previously controlled by the Japanese Navy, and prevented republicans from establishing an administration.