Lidia Thorpe has become the first Aboriginal person to represent Victoria in the Senate.
The Victorian state parliament on Friday confirmed Senator-elect Thorpe to fill a casual vacancy caused by the retirement of former Greens leader Richard Di Natale.
She said it was a shame it had taken so long for an Indigenous person to be elected to represent her state.
"When I was growing up in public housing, the thought that someone like me could be in parliament was laughable," she said.
"My promise to the people of Victoria is that I will fight for you, no matter who you are."
Senator-elect Thorpe said her priorities would be achieving a treaty and justice for Indigenous Australians, ending economic disadvantage and tackling climate change.
She is expected to be sworn in when the Senate next sits on October 6.