1 May 1945
Allied forces pushed north towards the Japanese home islands in 1945. Australian attention turned towards the liberation of lands closer to home, the Netherlands East Indies (Indonesia) in particular.
Initially planned as a series of 6 operations, Operation Oboe eventuated as 3 amphibious landings. They were code-named:
- Oboe One - the invasion of Tarakan island
- Oboe Six - the invasion of north Borneo at Labuan and Brunei
- Oboe Two - the invasion of Balikpapan.
Operation Oboe Two was the last large-scale Allied operation of the Second World War. It remains Australia's largest ever amphibious assault. Oboe Two was also the culmination of the Royal Australian Navy’s participation in over 20 south-west Pacific amphibious landings during the Second World War.
Oboe One commenced on 1 May 1945. There had been a heavy concentration of naval and air bombardment prior to the landing, as well as effective naval gunfire support. This effectively neutralised most Japanese resistance. Thus the landing was accomplished with marked success. The capture of Tarakan meant that, for the first time, all land and sea areas within the South West Pacific Command came under Allied air superiority.
Oboe Six proceeded to plan on 10 June 1945. Preliminary naval bombardment, hydrographic and mine clearance operations had taken place. Australian troops met little Japanese opposition, and moved rapidly to their first objectives. Naval gunfire support helped to reduce pockets of resistance on Labuan. The 9th Australian Division secured much of Brunei and British Borneo.
In July 1945, 2,000 regular Japanese troops and 3,000 local conscripts defended Balikpapan. They had little air, and effectively no naval, support. The Allies landed over 33,000 personnel along with their supplies and heavy equipment.
Mine-clearance operations at Balikpapan proved to be some of the most difficult of the war. Sweeping began on 15 June 1945 with 16 minesweepers and a covering force operating in shallow water, often under Japanese gunfire. Three minesweepers were sunk, 4 were damaged, 7 personnel were killed and 43 were wounded.
The landings went ahead on the morning of 1 July 1945. By noon that day, 10,500 troops, 700 vehicles and 1,950 tons of stores had been landed.
RAN units that took part in the Oboe series included:
- the RAN Beach Commando Unit
- the heavy cruiser HMAS Shropshire
- the light cruiser HMAS Hobart
- the destroyers HMAS Warramunga and Arunta
- the landing ships infantry HMA Ships Kanimbla, Manoora and Westralia
- the frigates HMA Ships Burdekin, Barcoo, Hawkesbury and Gascoyne
- several smaller support units.