The history of South Australia includes the history of the Australian state of South Australia since Federation in 1901, and the area's preceding Indigenous and British colonial societies. Aboriginal Australians of various nations or tribes have lived in South Australia for at least thirty thousand years, while British colonists arrived in the 19th century to establish a free colony. The South Australia Act, 1834 created the Province of South Australia, built according to the principles of systematic colonisation, with no convict settlers; after the colony nearly went bankrupt, the South Australia Act 1842 gave the British Government full control of South Australia as a Crown Colony. After some amendments to the form of government in the intervening years, South Australia became a self-governing colony in 1857 with the ratification of the Constitution Act 1856, and the Parliament of South Australia was formed. Meanwhile, European explorers were sent deep into the interior, discovering some pastoral land, but mainly large tracts of desert terrain. Sheep and other livestock were imported, wheat and other crops were grown where possible and a thriving viticulture industry was established. Copper was discovered. German Lutheran refugees set up mission stations and developed the wine industry in the Barossa Valley. The colony became a cradle of democratic and land reform in Australia. It was the first place in the world to institute the system of land registration known as Torrens title in 1858. Women were granted the vote in the 1890s. South Australia became a State of the Commonwealth of Australia in 1901 following a vote to federate with the other British colonies of Australia. While it has a smaller population than the eastern States, South Australia has often been at the vanguard of political and social change in Australia. Since World War II refugees and other migrants have boosted both the size and the multicultural nature of the population. Aboriginal settlement The first people to occupy the area now known as South Australia were Aboriginal Australians. Their presence in northern Australia began at least 65,000 years ago with the arrival of the first of their ancestors by land-bridge from what is now Indonesia. Their descendants moved south and occupied all areas of Australia, including the future South Australia. Temporary campsites in the Roxby dunefields have been dated to 19,000 years ago, and Aboriginal people have continuously occupied South Australian deserts since at least that time. Conservative estimates