[7] When Britain established its first Australian colony in 1788, the Aboriginal population is estimated to have been 300,000 to more than one million people[8][9][10] comprising about 600 tribes or nations and 250 languages with various dialects.

[11][12] In the 150 years that followed, the number of Aboriginal Australians fell sharply due to introduced diseases and violent conflict with the colonists that many scholars argue included acts of genocide.

Reserves were established and Church groups ran missions providing shelter, food, religious instruction and elementary schooling for Indigenous people.

Under the convention, genocide requires the perpetrator to commit acts with the intention to destroy, wholly or partly, "a national, ethnical, racial or religious group".

[3] Scholars have argued that acts of genocide against Indigenous Australians included: "Are we going to have a population of 1,000,000 blacks in the Commonwealth, or are we going to merge them into our white community and eventually forget that there ever were any aborigines in Australia?

"The near-destruction of Tasmania's Aboriginal population[45] has been described as an act of genocide by scholars including Robert Hughes, James Boyce, Lyndall Ryan, Tom Lawson, Mohamed Adhikari, Benjamin Madley, Ashley Riley Sousa, Rebe Taylor, and Tony Barta.

[49] However, other historians – including Henry Reynolds, Richard Broome, and Nicholas Clements – do not agree that the colonial authorities pursued a policy of destroying the Indigenous population, although they do acknowledge that some settlers supported extermination.

He concludes: "The colonial government from 1832 to 1838 ethnically cleansed the western half of Van Diemen's Land and then callously left the exiled people to their fate.

He says Arthur was determined to defeat the Aboriginal people and take their land, but believes there is little evidence he had aims beyond that objective and wished to destroy the Tasmanian race.

He says that unlike genocidal determinations by Nazis against Jews in World War II, Hutus against Tutsis in Rwanda and Ottomans against Armenians in present-day Turkey, which were carried out for ideological reasons, Tasmanian settlers participated in violence largely out of revenge and self-preservation.

[59] Lawson, in a critique of Reynolds' stand, argues that genocide was the inevitable outcome of a set of British policies to colonise Van Diemen's Land.

[69] Scholars are also divided over whether colonists and Australian governments acted with an intention to destroy Indigenous peoples in whole or in part and therefore committed genocide as defined by the UN convention.

[72] Others also argue that the high death toll among Indigenous Australians following colonisation was mainly a result of the introduction of diseases, and that deliberate acts of violence and the effects of dispossession did not meet the legal definition of genocide.

[79][80] Proponents of the genocide thesis, in turn, often accused their critics of denialism and ignoring the evidence of frontier massacres, the violent dispossession of Indigenous Australians of their land, and the systematic removal of Aboriginal children from their families.

[83][84] A watershed moment was the Bringing Them Home report, which contained the findings of the federal government inquiry into the removal of thousands of Aboriginal children.