On 26 January, 1788, the First Fleet of British ships arrived at Port Jackson, New South Wales, and Governor Arthur Phillip claimed the land for the crown of England.
The colonists assumed the land was terra nullius ('no one's land'), which Lt James Cook declared Australia to be in 1770 during his voyage around the coast of Australia.
In 1992, the High Court overturned the terra nullius fiction, but it also accepted the British assertion of sovereignty in 1788 and held that from that time there was only one sovereign power and one system of law in Australia.
People have begun referring 26 January by alternative terms such as Invasion day, Survival Day, and Day of Mourning, in a move to acknowledge the colonial past in a way that has never been done before.
These initiatives, says Karen Wyld in an article for The Ethics Centre website are not new.
“On 26 January 1938, on the 150th anniversary of the British invasion of this continent, a group of Aboriginal people in NSW wrote a letter of protest, calling it a Day of Mourning,” she writes.
“They asked the government to consider what that day meant to them, the First Peoples, and called for equality and justice.”
Thanks to a swelling grassroots movement, made more visible and vocal with the help of social media and the Internet, the idea of challenging the legitimacy of the day has pushed its way into the national spotlight.
The latest argument is that the date should be changed to find a neutral day which is inclusive of all Australians.
The hashtag #AlwaysWillBe has become a powerful rallying cry for Indigenous land rights.
The National Indigenous Television network interviewed film-maker Warwick Thornton, whose film Sweet Country is to be shown on 26 January.
He says the past must be discussed and Indigenous people finally have the talking stick. "Justice isn't served until we grow up as a country" he says.
Is a new date enough?
Luke Pearson, activist and founder of IndigenousX, doesn’t agree that changing the date goes far enough.
“You want a day to celebrate Australia. I want an Australia that’s worth celebrating,” he writes in an opinion piece for The Guardian on 16 January.
“This country’s treatment of its Indigenous population is so poor it does not deserve a party on any day ... Too many people [...] seem to think the problem with Australia Day rests solely on the day we celebrate it, not with what we are celebrating.
Pearson accuses the Australian government of only making cosmetic changes to calendar events in order to win over public opinion. He gives the example of the International Day of the Elimination of Racial Discrimination which became Harmony Day instead.
'Respect Australia Day'
Conservative Prime Minister Scott Morrison leads a group of politicians who want to keep Australia Day on 26 January.
"I'm not just going to not change it ... that's our historical day and we need to work together, to come together on that day to ensure that we can make it an important day for all Australians," Morrison said recently.
A new study by the Institute of Public Affairs found that support among the public is also high: three-quarters of those surveyed want Australia Day to remain as it is.
Only 10% of Australians think the date of Australia Day should be changed. Read the results of the new poll commissioned by the IPA: https://t.co/7j0spZ7hUGInstitute of Public Affairs (@TheIPA) 15 janvier 2019
Notably, support for keeping the date increases with age: 73 percent of Generation X (39-53 years) and 80 percent of Baby Boomers (54-72 years) were in favour, while the 73+ years bracket showed 90 percent support.
Figures were much lower among younger Australians. The 24-38 years group of respondents were 58 percent in favour of holding on to 26 January. Under 23 years, the figure fell to 47 percent.
Big Invasion Day turnout expected
More than 100,000 people are expected to turn out for Invasion Day rallies across the country this year.
In Sydney, there is the traditional Yabun event, the largest one-day gathering of Aboriginal and Torres Strait Islander cultures in Australia, featuring live music, kids’ activities and a corroboree ground.
In Melbourne, an Invasion Day protest has been organised and crowds are set to gather outside Parliament House before marching through the city streets.
The theme of this year’s march is not "change the date" but abolish Australia Day.
In the capital Canberra, the Invasion Day march is hosted by the Aboriginal Tent Embassy, a semi-permanent camp set up in 1972 on the lawn opposite Old Parliament House in Canberra.
Residing activists claim to represent the political rights of Aboriginal Australians.
It is not considered an official embassy by the Australian Government.