It is estimated that humans first arrived in Australia approximately 51,000 years ago[1] when ancestors of Australian Aborigines and Torres Strait Islanders arrived on the continent via the islands of Maritime Southeast Asia and New Guinea. Contact between aboriginal Australians and south Asian people, over the last 5000 years, led to interbreeding, and probably contributed to cultural change.[2] Europeans first landed in the 17th and 18th centuries, and colonisation by the British commenced in 1788.

Since 1945, more than 7 million people have come to Australia as new settlers. The trigger for a large-scale migration program was the end of World War II. Agreements were reached with Britain, some European countries and with the International Refugee Organization to encourage migration, including people displaced by the war in Europe. Approximately 1.6 million migrants arrived between October 1945 and 30 June 1960, about 1.3 million in the 1960s, about 960,000 in the 1970s, about 1.1 million in the 1980s, over 900,000 in the 1990s and over 900,000 since the year 2000.

Australia’s migrant population has historically been largely from a European background.[3]

The highest number of settlers to arrive in any one year since World War II was 185,099 in 1969–70. The lowest number in any one year was 52,752 in 1975–76.

Net overseas migration increased from 30,042 in 1992–93[4] to 177,600 in 2006–07.[5] The largest components of immigration are the skilled migration and family re-union programs. In recent years the mandatory detention of unauthorised arrivals by boat has generated great levels of controversy.

The 2011 Census reported that over one in four of Australia's 22 million people were born overseas. The number of settlers arriving in Australia from more than 200 countries between July 2008 and June 2009 totalled 158,021. Most were born in New Zealand (16.2 per cent), the United Kingdom (13.6 per cent), India (10.9 per cent), China (10.0 per cent) and South Africa (4.6 per cent).[6]

Migration program outcomes have increased from 70,200 in 1999–00 to 168,685 in 2010–11.[6]

A 2014 sociological study concluded that: "Australia and Canada are the most receptive to immigration among western nations".[7]

According to the Graduate Careers Survey,[8] full-time employment for newly qualified professionals from various occupations has declined since 2011.[9] The professional associations of some of these occupations have expressed their criticism of the immigration policy.[10]

Research published by The Daily Telegraph in 2012 shows that 51 per cent of respondents in favour of saying no to all migrants - a 10 per cent jump since 2005.[11]