Australian Army (Second World War)

Australian Army (Second World War)
Name	Australian Army (Second World War)
Active	1939–1945
Country	Australia
Branch	Army
Size	1,000,000 personnel (total served)
Notable commanders	Thomas Blamey, John Northcott, Leslie Morshead, Sydney Rowell

Australian Army (Second World War) The Australian Army during the Second World War was the principal land force of the Commonwealth of Australia, which expanded from a small prewar establishment into a large, multifaceted expeditionary and home defence force. It participated in campaigns across Europe, North Africa, the Mediterranean, the Middle East, Southeast Asia, and the Pacific, interacting with formations and leaders such as British Expeditionary Force (World War II), Eighth Army (United Kingdom), South West Pacific Area, Douglas MacArthur, and Winston Churchill. The army's wartime evolution reflected shifts in imperial strategy, regional security concerns, and technological and doctrinal changes exemplified by actions at Palestine (Mandatory) and Singapore.

Background and Mobilisation

At the outbreak of World War II in September 1939 the Australian Army comprised the small peacetime Australian Military Forces and the volunteer Second Australian Imperial Force (Second AIF) was raised for overseas service, responding to appeals from the British War Cabinet and the Commonwealth of Australia Parliament. Early mobilisation saw units deploy to the Middle East and the Mediterranean Sea, linking with formations such as the 2nd Australian Division (Second AIF), the 6th Australian Division, and allied corps under commanders including Thomas Blamey and Leslie Morshead. The entry of Japan into the war in December 1941 precipitated a dramatic reorientation: militia formations like the 2nd Australian Imperial Force (Citizen Military Forces) were mobilised for homeland defence and the government invoked wartime powers under statutes debated in the Parliament of Australia.

Organisation and Structure

The army's organisation combined the volunteer Second AIF expeditionary divisions with militia or Citizen Military Forces (CMF) brigades, organised into corps and command areas such as I Corps (Australia), II Corps (Australia), and the New Guinea Force. Command arrangements were affected by relationships with the British Chiefs of Staff Committee and later by the South West Pacific Area command under Douglas MacArthur, creating tensions between Australian high command figures like Sir Thomas Blamey and allied leadership. Specialist arms included the Royal Australian Artillery, Royal Australian Engineers, Royal Australian Army Medical Corps, Royal Australian Corps of Signals, and newly expanded units such as the 2/1st Anti-Tank Regiment and the 2/9th Field Regiment.

Major Campaigns and Operations

Australian formations fought at prominent battles in the North African Campaign including Siege of Tobruk, where the 9th Division and brigades under leaders such as Leslie Morshead earned distinction, and the El Alamein battles alongside the Eighth Army (United Kingdom). In the Mediterranean, Australians served in the Greece Campaign and the Crete Campaign against Wehrmacht operations. Following the Fall of Singapore and Kokoda Track campaign Australian forces, notably the 7th Division (Australia) and 39th Battalion (Australia), fought in New Guinea at Milne Bay, Lae, and the Huon Peninsula campaign, while the Australian Army took part in the liberation of Borneo during Operation Oboe. In the Pacific, Australian units worked with US formations in campaigns such as Aitape–Wewak and provided garrison duties in places including Papua and the Solomon Islands.

Home Front and Defence of Australia

Defensive priorities shifted after 1941 as fears of invasion rose following the Bombing of Darwin and Japanese advances in the Dutch East Indies. The CMF, fortified by emergency militia battalions and militia brigades, manned coastal defences around Sydney, Melbourne, and strategic ports, and participated in civil defence alongside organisations such as the Australian Women's Army Service and the Australian Red Cross. Infrastructure projects and construction by the Royal Australian Engineers supported bases in northern Australia and in an expanded logistics network linking to US facilities established under agreements with the United States of America.

Personnel, Equipment, and Training

Over one million Australians served in the army during the war, including infantry battalions like the 2/14th Battalion (Australia), armoured units such as the 1st Armoured Division (Australia), and specialised formations including the Z Special Unit and 2/1st Amphibious Support Regiment. Equipment evolution saw use of British and American materiel: vehicles including the Matilda II tank, artillery such as the Ordnance QF 25-pounder, small arms like the Lee–Enfield rifle, and later US-supplied M3 Stuart and M4 Sherman tanks. Training institutions, notably the Royal Military College, Duntroon and the Land Warfare Centre (Australia), adapted doctrine for jungle warfare, amphibious operations, and combined-arms tactics.

War Crimes, Discipline, and Legal Issues

Australian forces were involved in investigations and prosecutions related to conduct in combat, with inquiries into incidents such as alleged massacres and reprisal actions during campaigns in New Guinea and the Solomon Islands. Military tribunals under the Defence Act 1903 (Cth) and courts-martial addressed offences including desertion and murder, while postwar legal processes intersected with international mechanisms emerging from the London Charter of the International Military Tribunal. Other legal issues concerned the treatment of prisoners of war, exemplified by deaths in the Sanko Maru and transfer conditions involving Japanese forces.

Legacy and Postwar Transition

After 1945 the Australian Army demobilised rapidly, with many veterans reintegrating via schemes administered by agencies such as the Repatriation Department (Australia), and the organisation reconstituted into the postwar Australian Regular Army and CMF. Wartime experience influenced defence policy debates in the Australian Parliament, contributed to the establishment of alliances including the ANZUS Treaty, and left commemorations such as the Australian War Memorial and battle honours for units like the 9th Division (Australia). The army's wartime record shaped national identity, veteran advocacy through groups such as the Returned and Services League of Australia, and military doctrine during the early Cold War.

Category:Military history of Australia during World War II