Thousands of people breached Covid rules to protest against the culturally sensitive Australia Day holiday.
At least five arrests were made in Sydney at a rally attended by around 2,000 people, despite rules limiting the numbers allowed to gather at 500.
The day is controversial as it marks the start of Australia’s colonisation.
Australia Day is celebrated on 26 January, the anniversary of Britain’s First Fleet arriving in Sydney in 1788.
Branded by its critics as Invasion Day, it draws annual protest rallies drawing attention to the injustices faced by Indigenous people.
For years, a “change the date” campaign led by Indigenous Australians has lobbied to move the national day.
During the Sydney protest, demonstrators shouted “sovereignty was never ceded” and “no justice, no peace”, and held placards and banners reading “Not a Date to Celebrate” and “Black Lives Matter”.
Authorities had refused to waive the cap on numbers for the protests this year, despite no new infections being recorded in the city for more than a week.
Thousands more attended rallies in other cities across the country, with organisers asking protesters to maintain physical distance where possible and wear masks.
Despite the controversy around the day, the country’s Prime Minister Scott Morrison said the day represents how far Australia had come since the First Fleet arrived.
“There is no escaping or cancelling this fact,” he said at a ceremony in the capital Canberra. “For better and worse, it was the moment where the journey to our modern nation began.”