|This article needs additional citations for verification. (November 2009)|
|Type||Ad hoc formation|
|Size||~ 3–6 infantry battalions|
Maroubra Force was the name given to the Australian infantry force that defended Port Moresby, Papua New Guinea from the Japanese, and was involved in the Kokoda Track Campaign of the Pacific War, World War II. It was one of many units forming the body of the New Guinea Force, the main Allied army formation in the South West Pacific Area during 1942. Formed on 21 June 1942, it consisted of the Papuan Infantry Battalion, 39th Battalion and the 53rd Battalion and was under the command of Major General Basil Morris.
In mid-1942, the 39th Battalion, which had previously been deployed as a garrison force around Port Moresby, was sent overland via the Kokoda Track to secure the Buna area and prepare to oppose an enemy advance. The Papuan Infantry Battalion of about 280 native troops with white officers, was already north of the Owen Stanley Range at the entrance of the Kokoda Track. On 21 July 1942, the Japanese landed on the northeast coast of Papua and the Papuan Infantry Battalion was overwhelmed by the Japanese troops, and the entrance was captured on 29 July 1942.
Maroubra Force then successfully fought a month long delaying action through the debilitating terrain of the Owen Stanley Range, before being reinforced and finally driving off the Japanese just outside of Port Moresby. Maroubra Force was relieved by the 16th and 25th Brigades, which undertook the subsequent counter-offensive which drove the Japanese back to their beachheads at Buna, Gona and Sanananda on the Papuan north coast. At the Battle of Buna-Gona in November 1942–January 1943, Maroubra Force in turn relieved the 18th and 25th Brigades besieging Gona, and successfully crushed the Japanese beachhead there.
Maroubra Force was commanded first by Brigadier Selwyn Porter (30th Brigade),then Lieutenant-Colonel Ralph Honner (39th Battalion) and finally Brigadier Arnold Potts (21st Brigade). Brigadier Potts was later relieved of his command in controversial circumstances.
At its peak strength, Maroubra Force consisted of the 39th Battalion, the 53rd Battalion, and the 21st Brigade (2/14th Battalion, 2/16th Battalion and 2/27th Battalion). The 53rd Militia Battalion saw action briefly during the Battle of Isurava but was defeated and subsequently withdrew greatly demoralized, especially after the commanding officer and many senior officers of the 53rd were killed in action.
The Kokoda and Buna-Gona battles took a heavy toll on the soldiers of Maroubra Force. As an example, following both battles the 39th Battalion mustered barely 30 survivors (from a nominal strength of 600–800), the remainder either dead, missing, wounded, or in hospitals in Port Moresby and northern Australia suffering from disease and exhaustion. Maroubra Force, Lieutenant Colonel Honner, and Brigadier Potts were instrumental in the successful defence of Australia, and are sometimes cited as "the men who saved Australia", alongside the U.S. Admiral Frank J. Fletcher, whose actions at the Battle of the Coral Sea also staved off Japanese efforts to capture Port Moresby.
- The designation "2/_" refers to a battalion of the Second Australian Imperial Force, Australia's overseas volunteer force, which could be deployed anywhere. The Militia (also known as the Australian Citizens Military Forces), were Australia's reserve units, which consisted of both volunteers and conscripts and who, under the Defence Act (1903), were only able to be sent to fight in Australia and its overseas territories.
- "53rd Battalion (West Sydney Regiment)". Second World War, 1939–1945 units. Australian War Memorial. Retrieved 13 November 2009.