Why were Melba and the Little Rock Nine part of history?

The Little Rock Nine were a group of teenagers who agreed to integrate Little Rock High School in Arkansas. Arkansas, like other Southern states, practiced de jure, or legal, segregation. This included segregation in schools. The Supreme Court decision of Brown v. Board of Education of Topeka, Kansas (1954) undermined the "separate but equal" doctrine that had been established in the Supreme Court's decision of Plessy v. Ferguson (1896) by declaring that the wish to remain "separate" indicated inequality. The Supreme Court then issued another decision in 1955 to expedite the integration of Southern schools. Little Rock High School was one of the first to be integrated in 1957.
Melba Patillo Beals had a difficult experience, as did her fellow black classmate, Elizabeth Eckford, who was famously photographed being harassed on her way into the school. One of Eckford's harassers, Hazel Bryan, made efforts to distance herself from her racist past and tried to befriend Eckford. Beals writes about the relationship that she also formed with a white student at the school, though hers was during her time at Little Rock High—a romantic relationship which lasted as a friendship into adulthood.
Beals's narration of her experience in Warriors Don't Cry is useful for its illustration of both the public and personal aspects of the integration effort.