Linda Brown, who was at the centre of the 1950s court battle that led to the desegregation of US schools, has died aged 76.
"Linda Brown, lead plaintiff in our landmark Brown v. Board of Education case, has died," said the National Association for the Advancement of Colored People, which spearheaded the landmark legal effort.
"As a young girl, her courage in the face of one of the darkest forces in American history fundamentally changed our nation. For that, we owe her our eternal gratitude," it said.
Oliver Brown sought to enrol his daughter in an all-white school near the family's home in Topeka, Kansas, but was told she had to go to an all-black school that was further away.
Instead, Mr Brown turned to the courts for justice in a case that became part of an anti-segregation push by the NAACP rights group.
The Kansas case was combined with others from Delaware, South Carolina, Virginia, as well as the capital, Washington DC, when they were appealed to the US Supreme Court, becoming the ground-breaking Brown v Board of Education.
The US Supreme Court unanimously ruled on 17 May 1954 that segregation was unconstitutional, becoming a landmark moment in the US civil rights movement.
"A young girl from Topeka brought a case that ended segregation in public schools in America," Kansas governor Jeff Colyer wrote on Twitter.
"Linda Brown's life reminds us that sometimes the most unlikely people can have an incredible impact and that by serving our community we can truly change the world," Mr Colyer said.
RIP A hero for our nation!
— NAACP (@NAACP) March 26, 2018
Woman at center of Brown v. Topeka BOE case dies at 76 https://t.co/LMpS11HdJH#naacp
The American Civil Liberties Union rights group also hailed the impact of the Brown case, and Ms Brown herself.
"The Brown decision made America a beacon of hope to the rest of the world; it taught us that we could, through the rule of law, end a kind of oppression and race-based caste system," it said.
"Today we honour Linda Brown and all the fights we have left to win."
