The history of the Australian Army is the culmination of the Australian Army's predecessors and its 120-year modern history. The Army has its origins in the British Army and colonial military forces of the Australian colonies that were formed prior to the Federation of Australia. These were gradually united into federal units between 1899 and 1903; thus forming the beginning of the Australian Army. The colonial forces were combined and formed the basis of the new army, when the Commonwealth of Australia was founded on 1 January 1901. The modern history of the Army began with its founding at the start of the 20th century as the colonial armies were officially united as the Commonwealth Military Forces. In 1916 the title 'Australian Military Forces' was adopted and remained its official name until 1980, after which it became known as the Australian Army.
For more than 80 years after the establishment of the first British colony, the only professional soldiers in Australia were members of British regiments sent to garrison the continent. By the time that the garrisons were withdrawn in 1870, the six separate self-governing colonies in Australia already had their own separate, part-time reserve units, known as militia or "volunteers". Following economic hardships and subsequent industrial action that was broken up by the colonial forces, the Australian colonies became distrustful of permanent professional standing armies. They preferred a large citizen force and militia that was trained by a small professional force as a defence policy, compared to a large professional force that was supplemented by reserve forces, with this attitude lasting for an extensive period until the postwar period following World War II.[1][2]
The Australian Army has been involved in many international conflicts, including the Boer War, the First and Second World Wars, the occupation of Japan, the Korean War, the Malayan Emergency and Borneo Confrontation, the Vietnam War, and the wars in Afghanistan and Iraq.