Sacheen Littlefeather passed away at the age of 75, weeks after receiving an apology from the Academy of Motion Picture Arts and Sciences for its treatment of her during the 1973 Oscars, when she denied an Academy Award on behalf of Marlon Brando.

On Sunday October 2, according to the Academy of Motion Picture Arts and Sciences, Littlefeather passed away at her home in Novato, California.

Littlefeather was diagnosed with breast cancer.

Two weeks ago, the organization hosted an event in Littlefeather's name for an evening of "discussion, healing, and celebration."

Littlefeather, wearing a buckskin dress and moccasins, was the first Native American woman to ever take the stage at the Academy Awards when Brando received the best actor award for "The Godfather" in 1973.

Littlefeather, who was 26 years old when she appeared on Brando's behalf in 1973, told The Hollywood Reporter that Brando asked her not to touch the Oscar statuette and that show producer Howard Koch threatened to have her arrested if she spoke for more than 60 seconds.

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Littlefeather stated in her address that Brando cannot accept this extremely kind prize due to the treatment of American Indians by the film business, television movie reruns, and the recent events at Wounded Knee.

Some audience members jeered at her. Reportedly, John Wayne, who was backstage at the time, was enraged. Littlefeather claims she has been insulted, discriminated against, and personally abused in the years following her brief Academy Awards attendance.

In making the statement, the Academy Museum included a letter issued to Littlefeather by academy president David Rubin on June 18 regarding the memorable Oscar moment. Rubin described Littlefeather's remarks as a striking reminder of the imperative of respect and the significance of human dignity.

"The abuse you endured because of this statement was unwarranted and unjustified," wrote Rubin. "The emotional burden you have lived through and the cost to your own career in our industry are irreparable. 'For too long the courage you showed has been unacknowledged. For this, we offer both our deepest apologies and our sincere admiration."

Littlefeather told The Hollywood Reporter that she was "stunned" when the Academy asked her to make amends.

"I never thought I'd live to see the day I would be hearing this, experiencing this," Littlefeather told the outlet. "When I was at the podium in 1973, I stood there alone."