Bebop began to emerge in 1945, when Dizzy Gillespie recorded Be-Bop (also known as Dizzy’s Fingers) and Groovin’ High. The jazz press didn’t start using the term to define the entire genre until a year later, when a growing number of artists were recording in the style. While bop continued to develop in New York and Los Angeles, it wasn’t until late 1948 and ’49 that the style hit its popularity peak.

Why 1949? For one, the American Federation of Musicians and the recording industry had finally come to an agreement on contributions to a union fund meant to hire unemployed musicians displaced by technology. Once a deal was reached in the fall of ’48, radio stations were again free and clear to play records on the radio. This led to a jump in jazz DJs and programming.