Japanese occupation of the Dutch East Indies

The Empire of Japan occupied the Dutch East Indies (now Indonesia) during World War II from March 1942 until after the end of the war in September 1945.

In May 1940, Germany occupied the Netherlands, and martial law was declared in the Dutch East Indies. Following the failure of negotiations between the Dutch authorities and the Japanese, Japanese assets in the archipelago were frozen. The Dutch declared war on Japan following the 7 December 1941 attack on Pearl Harbor. The Japanese invasion of the Dutch East Indies began on 10 January 1942, and the Imperial Japanese Army overran the entire colony in less than three months. The Dutch surrendered on 8 March. Initially, most Indonesians welcomed the Japanese as liberators from their Dutch colonial masters. The sentiment changed, however, as between 4 and 10 million Indonesians were recruited as forced labourers (rōmusha) on economic development and defence projects in Java. Between 200,000 and 500,000 were sent away from Java to the outer islands, and as far as Burma and Siam. Of those taken off Java, not more than 70,000 survived the war. Four million people died in the Dutch East Indies as a result of famine and forced labour during the Japanese occupation, including 30,000 European civilian internee deaths.

In 1944–1945, Allied troops largely bypassed the Dutch East Indies and did not fight their way into the most populous parts such as Java and Sumatra. As such, most of the Dutch East Indies was still under occupation at the time of Japan's surrender in August 1945.

The invasion and subsequent occupation formed a fundamental challenge to Dutch colonial rule and brought about changes so extensive that the subsequent Indonesian National Revolution became possible. However, the Indonesian independence movement initially lacked international recognition, and following the surrender the Netherlands regained control of most of the Indies. A bitter five-year diplomatic, military and social struggle ensued, resulting in the Netherlands recognising Indonesian sovereignty in December 1949.