Actress and Native American civil rights activist Sacheen Littlefeather died at age 75 on Oct. 2.

Littlefeather was born on Nov. 14, 1946, to a Native American father of the Apache and Yaqui tribes and a white mother. At age three she was placed in the care of her maternal grandparents, as her own parents were not mentally stable enough to raise her.

She began a short-lived career in Hollywood during the 1970s when she played in movies like “The Trial of Billy Jack” and “Johnny Firecloud.”

However, Littlefeather is best known for her speech given at the 1973 Oscars on behalf of Marlon Brando. She met Brando after she had heard him speak in support of Native American rights while she was working for a radio station in San Francisco. After hearing his broadcast, Littlefeather decided to write a letter to him and Brando called her back which led to the pair becoming friends.

On the day of the Oscars, Brando had received word earlier that day that he had been nominated for Best Actor for his performance as Vito Corleone in the movie “The Godfather.” Brando had asked Littlfeather to reject the Oscar and had written an 8-page speech for her to read in his place if he won.

When Littlfeather arrived at the Oscars she was told that the speech was too long, leading to her improvising a new speech when she went up on stage.

Her new speech highlighted the poor treatment of Native Americans on television and in movies. Littlefeather also brought attention to the occupation going on at Wounded Knee, where members of the American Indian Movement seized the town of Wounded Knee, South Dakota.

During her speech, Littlefeather was met with mixed reactions of applause and boos. When she was escorted backstage after her speech, she was faced with criticism from celebrities like John Wayne, who was rumored to have been held back from attacking Littlefeather. These reactions led to her being blacklisted from Hollywood.

Aside from her speech at the Oscars, Littlefeather was also involved in protests for Native American rights, such as the Native Occupation of Alcatraz Island in 1969. This protest was done to bring attention to the violation of Native American rights by the U.S.  government.

After spending decades fighting for Native American rights, Littlefeather announced on Twitter that she was diagnosed with stage four terminal breast cancer which had spread to her lungs. She had spent the last few years of her life being involved with her community, and teaching Native American youth about their culture and heritage.

A few weeks before her death on Sept. 17, the Academy of Motion Picture Arts and Sciences issued a formal apology to Littlfeather for how she was treated at the 1973 Oscars. An event was also held where she was named the guest of honor. Littlfeather had replied saying that the apology was “long overdue.”