Rosa Parks. It’s a name everyone knows, synonymous with the Civil Rights movement, the woman who refused to move to the back of the bus and give her seat to a white man in Montgomery, Ala., in 1955. The act sparked a boycott, outrage across the nation. It became a symbol of a movement.

Parks was not the first African-American to take a stand. There were others: Lizzie Jennings, Homer Plessy, Irene Morgan, Claudette Colvin.

And then there was Sarah Keys. On Aug. 1, 1952, Keys, a private in the WAC (Women’s Army Corps) traveling down south from her base in Fort Dix, N.J., refused to give up her seat to a white Marine who had boarded the bus at a stop in Roanoke Rapids. An argument ensued and Keys was arrested and jailed. She was found guilty of the disorderly conduct charge and fined $25.

Enter Dovey Roundtree. Like Keys, Roundtree had served in the WAC during World War II. Like Keys, she’d also been evicted from a bus for the same reason, in Miami in 1943.

Roundtree and Julius Robertson, her law partner, took Keys’ case first to the U.S. District Court, then to the Interstate Commerce Commission. The battle of Keys v. Carolina Coach Company waged for three years. Initially, it was found that nondiscriminatory language of the Interstate Commerce Act said nothing about segregation — therefore it was not prohibited.

But elsewhere in the courts, the ball had started rolling: the Supreme Court handed down the Brown v. Board of Education decision, a landmark Civil Rights case, ruling that the 14th amendment prohibited segregation in the schools. When Roundtree filed exceptions to the ICC’s finding, she used the Supreme Court’s own reasoning in Brown for her arguments.

A year later, the ICC came around, banning segregation on interstate buses: “We conclude that the assignment of seats on interstate buses, so designated as to imply the inherent inferiority of a traveler solely because of race or color, must be regarded as subjecting the traveler to unjust discrimination, and undue and unreasonable prejudice and disadvantage … and is therefore unlawful.”

A week after that, Rosa Parks refused to give her seat up on a Montgomery bus. And people like Keys, cases like Keys v. Carolina Coach Company, paved the way for Parks’ stance.

So where was Sarah Keys going that night as she traveled south to become a part of history, paving the way for Civil Rights movement? Well, she was going home. Home to Washington, North Carolina.