January 26 has been commemorated as a Day of Mourning by First Peoples since 1938.
More background information here.
Quotes attributable to Lidia Thorpe, Gunnai, Gunditjmara and Djab Wurrung independent Victorian Senator:
"January 26 is a National Day of Mourning for First Peoples, that is not up for debate.
"For First Peoples, January 26 marks the beginning of invasion, the start of dispossession, forced removal, and violence. That is why, in 1938, Yorta Yorta leader William Cooper and other Aboriginal leaders organised a silent march in Sydney to commemorate January 26 as a national Day of Mourning.
"Eighty-eight years on, governments still have not recognised it as such. But that doesn’t change anything. The meaning of this day for First Peoples cannot be granted or taken away. It is already real, already true, and already lived.
"We do not need permission to mourn. We do not need permission to remember. We do not need permission to tell the truth. And we do not need governments to officially recognise January 26 as a Day of Mourning. It would be the respectful thing for them to do, but it would not change the meaning of the day for us.
"We are sick of the culture war that happens every year while we are trying to mourn. People in this country need to accept that First Peoples will not stop mourning on January 26 because others want to celebrate. We will not stop marking this day, and we will not stop telling the truth.
"The discussion about the national holiday is one that those who want to celebrate it should have. Do they want a national holiday that is inclusive — one that does not clash with a day of mourning and does not create the same yearly division? Or do they want to continue as usual, celebrating on our Day of Mourning to prove a point?
"The debate about nationalistic celebrations on January 26 is not one First Peoples need to be a part of. We already know what today means. This is a debate non-Indigenous people in this country must have among themselves. Leave us out of it.
"If governments want to move the national holiday to a day that does not coincide with our Day of Mourning, that is their choice.
"What we ask of non-Indigenous people in this country is simple: learn what January 26 means for First Peoples, respect and commemorate this solemn day with us, and join us in solidarity at the many events held around the country each year.
"More and more people in this country are coming to understand that January 26 is a Day of Mourning. And each year, more people respect this and walk with us. Not because they were told to, but because they understand the truth and they know it’s the right thing to do."