The name "Australia" was popularised by the 1814 work A Voyage to Terra Australis by the navigator Matthew Flinders, the first recorded person to circumnavigate Australia. Though its title reflected the British Admiralty's usage, Flinders used the word "Australia" in his book, and because it was widely read it gave the term general currency. Governor Lachlan Macquarie of New South Wales subsequently used the word in his dispatches to England, and on 12 December 1817 recommended to the Colonial Office that it be officially adopted. In 1824, the Admiralty agreed that the continent should be known officially as "Australia".

The first human habitation of Australia is estimated to have occurred between 42,000 and 48,000 years ago. These first Australians were possibly the ancestors of the current Indigenous Australians; they may have arrived via land bridges and short sea-crossings from present-day South-East 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; their cultural practices were and remain distinct from those of the Aborigines.
The first recorded European sighting of the Australian mainland was made by the Dutch navigator Willem Janszoon, who sighted the coast of Cape York Peninsula in 1606. During the 17th century, the Dutch charted the whole of the western and northern coastlines of what they called New Holland, but they 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 Great Britain. The expedition's discoveries provided impetus for the establishment of a penal colony there.

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 was founded in 1911 when it was excised from 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 the colony of New South Wales ceased in 1848 after a campaign by the settlers.
The Indigenous Australian population, estimated at 350,000 at the time of European settlement, declined steeply for 150 years following settlement, mainly because of infectious disease combined with forced re-settlement and cultural disintegration. The removal of children from their families, which some historians and Indigenous Australians have argued could be considered to constitute genocide by some definitions, may have contributed to the decline in the indigenous population. Such interpretations of Aboriginal history are disputed by some commentators 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 1992, when the High Court case Mabo v Queensland (No 2) overturned the notion of Australia as terra nullius (lit. "land of none" or "empty land") at the time of European occupation.
A gold rush began in Australia in the early 1850s, and the Eureka Stockade rebellion against mining licence fees in 1854 was an early expression of civil disobedience. 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. The Commonwealth of Australia was born as a Dominion of the British Empire. The Federal Capital Territory (later renamed the Australian Capital Territory) was formed from a part of New South Wales in 1911 to provide a location for the proposed new federal capital of Canberra (Melbourne was the temporary seat of government from 1901 to 1927 while Canberra was being constructed). 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. The Kokoda Track Campaign is regarded by many as an analogous nation-defining event during World War II.
The Statute of Westminster 1931 formally ended most of the constitutional links between Australia and the United Kingdom when Australia adopted it in 1942, but backdated it to the beginning of World War II to confirm the validity of legislation passed by the Australian Parliament during the war. 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 immigration from Europe; since the 1970s and the abolition of the White Australia policy, immigration from Asia and other non-European parts of the world was also encouraged. As a result, Australia's demography, culture and self-image have been transformed. The final constitutional ties between Australia and the UK were severed in 1986 with the passing of the Australia Act 1986, ending any British role in the government of the Australian States, and ending judicial appeals to the UK Privy Council. In 1999, Australian voters rejected by a majority of 54% a move to become a republic with a president appointed by two-thirds vote of both houses of the Australian Parliament. To alter the Australian constitution an Act of the Australian Parliament must occur as well as a referendum receiving not only a majority of votes across the country, but also a majority of votes in a majority of the six Australian states. The referendum of 1999 not only did not receive a majority of votes across the country, it also did not win one of the six Australian states. Since the election of the Whitlam Government in 1972, there has been an increasing focus on the expansion of ties with other Pacific Rim nations while maintaining close ties with Australia's traditional allies and trading partners.
Australia has six states, two major mainland territories, and other minor territories. The states are New South Wales, Queensland, South Australia, Tasmania, Victoria, and Western Australia. The two major mainland territories are the Northern Territory and the Australian Capital Territory (ACT). In most respects, the territories function like the states, but the Commonwealth Parliament can override any legislation of their parliaments. By contrast, federal legislation only overrides state legislation in certain areas that are set out in Section 51 of the Australian Constitution; state parliaments retain all residual legislative powers, including powers over hospitals, education, police, the judiciary, roads, public transport, and local government.
Australia's 7,617,930 square kilometres (2,941,299 sq. mi) landmass is on the Indo-Australian Plate. Surrounded by the IndianN4 and Pacific oceans, Australia is separated from Asia by the Arafura and Timor seas. Australia has 34,218 kilometres (21,262 mi) of coastline (excluding all offshore islands) and claims an extensive exclusive economic zone of 8,148,250 square kilometres (3,146,057 sq. mi). This exclusive economic zone does not include the Australian Antarctic Territory.
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