The first human habitation of Australia is estimated to have occurred between 42,000 and 48,000 years ago. The first Australians were the ancestors of the current Indigenous Australians; they arrived via land bridges and short sea-crossings from present-day Southeast Asia. Most of these people were hunter-gatherers, with a complex oral culture and spiritual values based on reverence for the land and a belief in the Dreamtime. The Torres Strait Islanders, ethnically Melanesian, inhabited the Torres Strait Islands and parts of far-north Queensland; they possess distinct cultural practices from the Aborigines.
The first undisputed recorded European sighting of the Australian continent was made by the Dutch navigator Willem Jansz, who sighted the coast of Cape York Peninsula in 1606. During the seventeenth century, the Dutch charted the whole of the western and northern coastlines of what they called New Holland, but made no attempt at settlement. In 1770, James Cook sailed along and mapped the east coast of Australia, which he named New South Wales and claimed for Britain. The expedition's discoveries provided impetus for the establishment of a penal colony there following the loss of the American colonies that had previously filled that role.
The British Crown Colony of New South Wales started with the establishment of a settlement at Port Jackson by Captain Arthur Phillip on 26 January 1788. This date was later to become Australia's national day, Australia Day. Van Diemen's Land, now known as Tasmania, was settled in 1803 and became a separate colony in 1825. The United Kingdom formally claimed the western part of Australia in 1829. Separate colonies were created from parts of New South Wales: South Australia in 1836, Victoria in 1851, and Queensland in 1859. The Northern Territory (NT) was founded in 1863 as part of the Province of South Australia. South Australia was founded as a "free province" - that is, it was never a penal colony. Victoria and Western Australia were also founded "free", but later accepted transported convicts. The transportation of convicts to Australia was phased out between 1840 and 1864.
The Indigenous Australian population, estimated at about 350,000 at the time of European settlement, (Estimates for the total Aboriginal population in 1788 vary. Current estimates based on archaeological research range between 500,000 and 1 million) declined steeply for 150 years following settlement, mainly because of infectious disease combined with forced re-settlement and cultural disintegration. The removal of children, that some historians and Indigenous Australians have argued could be considered to constitute genocide by today's understanding, may have made a small contribution to the decline in the indigenous population. Such interpretations of Aboriginal history are disputed by some as being exaggerated or fabricated for political or ideological reasons.This debate is known within Australia as the History Wars. Following the 1967 referendum, the Federal government gained the power to implement policies and make laws with respect to Aborigines. Traditional ownership of land - native title - was not recognised until the High Court case Mabo v Queensland (No 2) overturned the notion of Australia as terra nullius at the time of European occupation.
A gold rush began in Australia in the early 1850s, and the Eureka Stockade rebellion in 1854 was an early expression of nationalist sentiment. Between 1855 and 1890, the six colonies individually gained responsible government, managing most of their own affairs while remaining part of the British Empire. The Colonial Office in London retained control of some matters, notably foreign affairs, defence and international shipping. On 1 January 1901, federation of the colonies was achieved after a decade of planning, consultation and voting, and the Commonwealth of Australia was born, as a Dominion of the British Empire. The Australian Capital Territory (ACT) was formed from New South Wales in 1911 to provide a location for the proposed new federal capital of Canberra (Melbourne was the capital from 1901 to 1927). The Northern Territory was transferred from the control of the South Australian government to the Commonwealth in 1911. Australia willingly participated in World War I; many Australians regard the defeat of the Australian and New Zealand Army Corps (ANZACs) at Gallipoli as the birth of the nation - its first major military action. Much like Gallipoli, the Kokoda Track Campaign is regarded by many as a nation-defining battle from World War II.
The Statute of Westminster 1931 formally ended most of the constitutional links between Australia and the United Kingdom, but Australia did not adopt the Statute until 1942. The shock of the United Kingdom's defeat in Asia in 1942 and the threat of Japanese invasion caused Australia to turn to the United States as a new ally and protector. Since 1951, Australia has been a formal military ally of the US under the auspices of the ANZUS treaty. After World War II, Australia encouraged mass immigration from Europe; since the 1970s and the abolition of the White Australia policy, immigration from Asia and other parts of the world was also encouraged. As a result, Australia's demography, culture and image of itself were radically transformed. The final constitutional ties between Australia and the United Kingdom ended in 1986 with the passing of the Australia Act 1986, ending any British role in the Australian States, and ending judicial appeals to the UK Privy Council. Australian voters rejected a move to become a republic in 1999 by a 55% majority. Since the election of the Whitlam Government in 1972, there has been an increasing focus on the nation's future as a part of the Asia-Pacific region.