Jazz music’s popular rise during the early half of the 20th century helped pave the way for the civil rights movement of the 60s. The music’s appeal was universally enjoyed by people regardless of race or political belief. 

As early as the 1920s, black and white jazz musicians would play together secretly in after-hours jam sessions.  Benny Goodman in 1935 was the first to hire a black musician to be part of his group, contrary to segregation laws and social norms.   By the 1940s more and more bands were performing publicly with both black and white musicians.  And it wasn't just the bands that were getting along, it was the audience:

Louis Armstrong wrote about one of his "most inspiring moments" in a 1941 letter to a jazz critic: "I was playing a concert date in a Miami auditorium. I walked on stage and there I saw something I’d never seen. I saw thousands of people, colored and white, on the main floor. Not segregated in one row of whites and another row of Negroes. Just all together naturally. I thought I was in the wrong state. When you see things like that, you know you’re going forward.” 

According to Michael Verity (jazz historian), jazz “provided a culture in which the collective and the individual were inextricable, and in which one was judged by his ability alone, and not by race or any other irrelevant factors."  

Jazz historian Stanley Crouch said, “Once the musicians who played it and the listeners who loved it began to balk at the limitations imposed by segregation, jazz became a futuristic social force in which one was finally judged purely on the basis of one’s individual ability. Jazz predicted the civil rights movement more than any other art in America.”

Enjoy this video showcasing the first integrated band, the Benny Goodman Quartet with Teddy Wilson, Lionel Hampton and Gene Krupa with "I Got A Heartful Of Music".