Final answer:
Hard bop was seen as a movement that returned to the roots of jazz by drawing from blues, gospel, and rhythm and blues. It was a reaction against more commercialized jazz and emphasized African American cultural heritage through soulful improvisation and melodies. The hard bop school often explained its development as a return to the roots of jazz.
Step-by-step explanation:
Hard bop was a movement that emerged in the 1950s, characterized by its embrace of African American culture and its musical heritage. This style of jazz was seen as a reaction to the more commercialized forms of jazz that had started to emerge. Hard bop musicians sought to express the reality and soul of their experiences with a more gospel-inspired flavor and rhythmically intense approach to improvisation.
The musical roots to which hard bop returned were embedded in the African American experience, drawing from blues, gospel, and rhythm and blues. These genres possessed distinctive features such as blues scales, improvisation, and a focus on expressive, soulful melodies and were integral to the formation of early jazz styles in places like Harlem, as exemplified by legends such as Louis Armstrong and Charlie Parker. With hard bop, musicians like Horace Silver, Art Blakey, and Miles Davis built upon these traditions, adding their own innovations to create a robust and dynamic jazz subgenre.
Witnessing the development of hard bop as a manifesto of this traditional authenticity, signifies not only a nod to historical forms but also a continuation and evolution of jazz's inherent spirit of innovation and cultural expression. In essence, hard bop was both a return to the origins and a step forward, enriching jazz's tapestry with new rhythms and harmonies.