The White Australia policy comprises various historical policies that intentionally restricted "non-white" immigration to Australia from 1901 to 1973.

Competition in the goldfields, labour disputes and Australian nationalism created an environment of racial antagonism during the second half of the 19th century which led to the passage of the Immigration Restriction Act in 1901, one of the first Acts of the new national parliament upon federation. The passage of this bill is considered the commencement of the White Australia Policy as Australian government policy. Subsequent acts further strengthened the policy up to the start of World War II.

The policy was dismantled in stages by several successive governments after the conclusion of World War II, with the encouragement of first non-British and later non-white immigration. From 1973 on, the White Australia policy was for all practical purposes defunct, and in 1975 the Australian government passed the Racial Discrimination Act, which made racially-based selection criteria illegal.

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Between the Great Depression starting in 1929 and the end of World War II in 1945, global conditions kept immigration to very low levels.[11] At the start of the war, Prime Minister John Curtin (ALP) reinforced the message of the White Australia Policy by saying: "This country shall remain forever the home of the descendants of those people who came here in peace in order to establish in the South Seas an outpost of the British race."[12]

However, by the end of World War II, Australia's vulnerability during the war in the Pacific and small population led to policies summarised by the slogan, "Populate or Perish", an ethnocentric slogan that meant "Fill with whites, lest we be filled with yellows".[13] During the war, many non-white refugees, including Malays, Indonesians, and Filipinos, had settled in Australia, but Immigration Minister Arthur Calwell controversially sought to have them all deported. In 1948, Iranian Bahá'ís seeking to immigrate to Australia were classified as "Asiatic" by the policy and were denied entry.[14] In 1949, Calwell's successor Harold Holt allowed the remaining 800 non-white refugees to apply for residency, and also allowed Japanese "war brides" to settle in Australia.[12] In the meantime, encouraging immigration from Europe, Australia admitted large numbers of immigrants from mostly Italy, Greece, and Yugoslavia, as well as its traditional source of the British Isles.

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http://en.wikipedia.org/wiki/White_Australia_policy