Johnnie Rebecca Carr, one of the lesser-known leaders of the civil rights movement, died Friday in Montgomery, Ala.

For decades, Carr led the Montgomery Improvement Association, an organization formed in 1955 when Carr’s childhood friend Rosa Parks was arrested for refusing to give up her bus seat to a white man. The moment sparked the Montgomery bus boycott, and drew national attention to the fight against segregation and a local minister named Martin Luther King Jr.