Throughout the 1600s and 1700s Britain had a major problem with crime and criminals. Many people convicted of crimes (including petty crimes such as theft) were sentenced to be transported to America. In the 1770s the American colonies revolted against Britain. This meant that Britain had nowhere to send its convicts and turned towards Australia. The first convict colonies of Van Diemen's Land (now Tasmania) and New South Wales were set up in the 1780s.
It is difficult for us to imagine how hard life was for the early convicts. The greatest hardship was being torn away from their homes and families, almost certainly never to see them again. Australia was a harsh and unfamiliar environment, with its hot climate and weird animals. Then there was the brutal discipline of the convict colonies. The evidence suggests that Van Diemen's Land was run more harshly than New South Wales. This is partly because Van Diemen's Land received many of the prisoners considered troublesome, such as Irish and Canadian rebels who tried to overthrow British rule in the 1830s and 1840s. It was also due to the attitudes of the governors of each area. In New South Wales the convicts were generally in great demand because there was a tremendous shortage of labour. Once they had served their sentences they could apply for grants of land and become settlers. Most convicts did not return to Britain as life in Australia presented them with better possibilities.
Transportation to Australia ended in 1852, although convict labour was still used in Australia until 1867. Transportation ended for several reasons. One was a campaign against its cruelty (in Britain and Australia). Another was that the growing population of settlers began to see themselves as 'Australians' and began to resent Britain dumping its poorest and most troubled people in their country. A further reason was that as emigration of free people to Australia grew, there was less need for convict labour.