Australia became a self-governing dominion of the British Empire in 1901. Although the federal government was appointed by a British governor, the two-tier parliament was elected by adult suffrage. Unlike in Britain, Australian women were granted the vote in 1902.
By the beginning of the 20th century the population of around 5 million was mainly concentrated on the coast but an estimated 200,000 native Australians were living in the interior. The Immigration Restriction Act of July 1902 imposed a linguistic ability test so as to maintain what became known as a 'White Australia' policy.
The Australian Army was formed in 1901. It was a very small army and was organism solely for home defence. The regular army was backed-up by a part-time volunteer militia (45,000 men in 1914). All males of combat age were required by law to undertake military training.
During the First World War Australia contributed 322,000 soldiers, of whom more than 280,000 were casualties. Just under 60,000 Australians were killed, the highest death-rate suffered by any national army in the war.
On the outbreak of the Second World War the prime minister of Australia, Sir Robert Menzies, immediately announced that its armed forces would support the Allied war effort. This policy continued under John Curtin, the leader of the Australian Labour Party, who gained power in 1941.
Compulsory military service was introduced with the understanding that conscripts would be required to serve only in Australia and it's territories. Recruitment for the three main services took place and concerned about only having 164 combat aircraft efforts were made to supplement this force.
Two divisions (6th and 7th) of the Australian Imperial Force (AIF) under Lieutenant-General Thomas Blamey were sent to Palestine for training. These soldiers were expected to be sent to France but after its surrender in June 1940 they were sent to North Africa instead.
About 560,000 members of the Australian Imperial Force (AIF) served overseas during the Second World War. The Australian Air Force saw action over Europe and the Navy fought with the Royal Navy in the Mediterranean and the Sydney sunk the Italian cruiser Bartolomeo Colleoni.
After the Japanese attack on Pearl Harbor and the invasion of New Guinea, the Australian armed forces worked closely with those of the United States under the leadership of General Douglas MacArthur, who had established his headquarters in Brisbane. John Curtin announced that "without inhibitions of any kind, I make it clear that (from now on) Australia looks to America, free of any pangs as to our traditional links or kinship with the United Kingdom."
The Japanese Air Force made 14 air raids on Darwin in early 1942. Later the Japanese mounted raids against towns in the Northern Territory and Western Australia. In May 1942 Japanese submarines made an unsuccessful attempt to enter Sydney Harbour.
John Curtin began to fear that the Japanese Army would attempt to invade Australia and against the wishes of Winston Churchill recalled two divisions of the Australian Imperial Force from the Middle East.