Global Citizen started here in on Naarm lands in the Kulin nation, after Nelson Mandela gave a speech to Australians with an appeal to build a new South Africa based on reconciliation between black and white Africa.

Last week, I delivered a speech to millions of global citizens in the presence of royalty on the same topic, this time for Australia. Wearing my Buka cloak from my Noongar homeland, I wasted no time to speak my agenda as the referendum campaign and its outcome has taught me to do more than ever before. It was also my 34th birthday, and looking back on my career of activism and progress I've decided I don't have time to lose or anything to hold back on.

"For as long as the Crown of Terra Nullius remains, we cannot advance as a nation."

When I said these words, the silence concerned me. Until I looked down into the audience and saw a young man with tears in his eyes. I continued to call for reconciliation, First Nations constitutional recognition, and a republic based on First Nations governance because of our great 60,000-year significance. Empires fall across centuries while the sustainable Indigenous cultural practices of the world remain, even after efforts to disrupt or eliminate them.

That night at a Global Citizen Nights concert featuring Nooky, 3% and Crowded House, the Duchess of York acknowledged Aboriginal and Torres Strait Islander people for the first time on record and apologised in a heartfelt way, which shocked, humbled, and moved me personally. Nooky performed with the images of Aboriginal men in chains on screen and when I saw the horror and immediate sadness in the Duchess' face from the main audience where she sat as an equal with us, I knew that Nooky had made an impact.

I have been advocating for constitutional transformation for a decade. My doctoral research - which I was invited to speak on - is on a model for an Australian Republic which must acknowledge First Nations people in the aftermath of the Voice referendum defeat. I had received mockery and even ridicule from racists, even a smaller number of my own mob, since the defeat at the polls.

I've had my role in cultural knowledge and even my race questioned by people who once celebrated me and included me despite my appearance as a mixed race man. That hurt deeply, but the hypocrisy of it all spoke clearly to me that I was on the correct path; Not a path of ignorance.

I know I have not disappointed my people in simply trying to alleviate systemic poverty. It is too easy to sit by and say 'nothing can be done' and this has continued for far too long by so called leaders of ours, who profit and serve themselves rather than seek opportunities for mob. I am proud of my role with the Uluṟu Statement and will continue to call for these reforms.

At the end of the day, while many said I was a dreamer in my decade-long fervour for constitutional transformation, I managed to speak at a forum with royalty and I played my part in influencing change through respect - and an inability to back down - which seems to have served us all well. The King's sister-in-law now honours us, respects us, and is truly sorry for the past injustices and current ones. She wants to do something and she said to delegates that she would put pressure anywhere she could, for governments to give First Nations Australians the voice we deserve.

This year, the King may tour Australia. His Majesty is ill and yet he still stands for climate and other social justice causes. He has acknowledged the need for Commonwealth nations to become independent. He is forward looking and seems to care. We wish good health and prosperity for his descendants in his own homelands, and he will be welcome on ours as an equal. As we welcome all good people to our lands.

I would hope that he acknowledges First Nations sovereignty as well, and that he is aware that our coming generations need change. We may walk as equal partners, but no longer subjects.

Jesse J. Fleay is a Noongar writer and research specialist across major policy areas. His doctoral thesis explores a model for an Australian republic, along with calls to enact a Voice to Parliament for First Nations Australians. He believes in justice, and fairness in society and only works with people committed to First Nations people, and their self-determination. Views expressed are his own.