The Japanese advance in the Asia-Pacific in late 1941 and early 1942 was one of the most dramatic periods of conquest in modern military history …
In just five months Japanese forces occupied territory that stretched from British Burma (now Myanmar) in the west to the American Wake Island in the east.
The Japanese invasion of Manchuria in 1931 was the start of an expansionist policy aimed at creating a Greater East Asia Co-Prosperity Sphere. In 1937 Japan attacked China and in the following two years occupied much of northern China and key coastal regions. When France was defeated by Nazi Germany in 1940, Japan also occupied the French colonies in Indochina.
In response to Japanese aggression the United States imposed an oil and economic embargo in 1941. In turn the Japanese decided on a southward expansion to gain strategic resources from South East Asia and the Netherlands East Indies (now Indonesia). Other areas such as Papua New Guinea and various Pacific Islands were to be captured to provide a protective barrier against Allied counterattack.
Despite having feared war with the Japanese in the Pacific for some time, Australia and Great Britain were unprepared to meet the growing threat since they were preoccupied with the war against Germany and Italy. Nonetheless in 1941 two brigades of the 8th Division of the 2nd Australian Imperial Force were based in Malaya alongside British and Indian troops. A further three battalions of the Division's third brigade would be divided between the islands of Timor, Ambon and New Britain.
On 7 December 1941 the Japanese launched a pre-emptive and surprise attack on the United States naval base at Pearl Harbor, thus bringing the United States into the war on the Allies' side. At the same time, Japanese forces landed in Thailand and Malaya and began rapidly advancing down the Malayan peninsula. They also attacked the British colony of Hong Kong and the US-controlled islands of Guam, Wake and Midway.
The better-led and experienced Japanese troops had complete air superiority and rapidly pushed the British, Indian and Australian troops southward toward Singapore. Despite some local tactical successes, such as at Gemas, Bakri and Jemaluang, the imperial forces could not stop the Japanese advance. Singapore fell on 15 February 1942. Over 130 000 Allied troops, including over 15 000 Australians, became prisoners of war.
From late 1941 onwards Japanese forces also successfully attacked the Philippines, New Britain, the Netherlands East Indies and Burma.
In mid-February some units of the Australian 7th Division were landed in Java in an effort to stop the Japanese advance. But they too were captured after brief fighting, together with the survivors of the sinking of the HMAS Perth and the USS Houston in the Sunda Strait on the night of 28 February–1 March 1942.
By early March 1942 the Japanese conquered Rangoon, Burma and were threatening the British in India. American resistance in the Philippines all but ended in April, after which Japanese forces moved to consolidate their conquests by capturing a buffer zone of territory in Papua New Guinea, the Solomon Islands and in the Pacific.
However, during the Battle of the Coral Sea from 5–8 May 1942 Australian and American naval forces turned back Japanese transports and warships aiming to capture Port Moresby. This reversal necessitated the Japanese attempt to advance overland across the Owen Stanley Ranges along the Kokoda track.
One month later from 4–7 June the United States Navy fought and won a massive naval battle near the Pacific island of Midway. This was a severe blow to Japanese naval power. While not defeated, the Imperial Japanese Navy was now stretched in its ability to control the seas around the territories it had conquered.
The shipping lane through the Malacca Straits off Malaya was one such route. In order to reduce the requirement for naval escorts the Japanese therefore decided to construct a railway connecting their frontline in Burma with Japanese forces and supplies in Thailand and Malaya. In keeping with the goal of freeing up resources for other fronts, the Japanese military decided to use prisoners of war and local labour to build this railway.