Martha White, a Black woman who helped launch the 1953 bus boycotts in Louisiana by daring to sit in a seat reserved for white passengers, has died at age 99.

White, whose activism foreshadowed the civil rights era to come, died Saturday, her family confirmed.

White, then 31, was working as a housekeeper in the capital city of Baton Rouge in 1953 when she took action. After a long day of walking to and from work to reach her bus stop, she decided to sit in a bus seat designated for white passengers.

When the driver ordered her to get up, White refused and another Black woman sat beside her in solidarity. The bus driver threatened to have the women arrested.

Ultimately police, the bus company manager and a civil rights activist, the Rev. T.J. Jemison, showed up. Jemison informed the driver of a recently passed ordinance to desegregate buses in the city, meaning White wasn’t violating any rules. In response to the ordinance, bus drivers began a strike and the ordinance was later overturned. That prompted a boycott by the Black community in Baton Rouge.

Baton Rouge Mayor Sharon Weston Broome issued a statement Monday recognizing White’s contribution to the city’s civil rights movement.

“Martha White undoubtedly shaped our community in Baton Rouge, and communities across our nation,” Broome said.

That boycott later helped provide the framework for the famous effort sparked by Rosa Parks that led to a bus boycott in Montgomery, Ala., in 1955.

Ted Jemison, the son of the Rev. T.J. Jemison, remembered White as being outspoken and unafraid to share her opinion.

He told the Advocate about a conversation he had with her years ago about that day in 1953. He recalled her telling him that she just wanted to sit in that bus seat because she was tired from being on her feet.

“ ‘Can you imagine working on your feet all day and just wanting to sit down?’ ” Jemison recalled White as saying. “She was the same way from when she was young to when she was 90 years old. She knew that what she did was for the good of everyone.”

“We really lost a true pioneer for civil rights,” said Jason Roberts, co-owner of the Baton Rouge African American Museum, speaking of White’s death, the newspaper reported.