So named because it served as the basis of music later developed in the United States, including rock and roll, rhythm and blues and jazz.

Many roots musicians do not consider themselves to be folk musicians. The main difference between the American folk music revival and American roots music is that the latter seems to cover a slightly broader range, including blues and country.

Roots musical forms reached their most expressive and varied in the first two to three decades of the 20th century. The Great Depression and the Dust Bowl were extremely important in disseminating these musical styles to the rest of the country, as Delta blues masters, itinerant honky tonk singers and Latino and Cajun musicians spread to cities like Chicago, Los Angeles and New York.

The growth of the recording industry in the same approximate period was also important, placing pressure on artists, songwriters and label executives to replicate previous hit songs. This meant that fads like Hawaiian slack-key guitar never died out completely as rhythms or instruments or vocal stylings were incorporated into disparate genres.

By the 1950s, all the forms of roots music had led to pop-oriented forms. Folk musicians like the Kingston Trio, pop-Tejano and Cuban-American fusions like boogaloo, chachacha and mambo, blues-derived rock and roll and rockabilly, pop-gospel, doo wop and R&B (later secularised further as soul music) and the Nashville sound in country music all modernised and expanded the musical palette of the country. Many musicians identify themselves as roots musicians to avoid being pidgeon-holed into a particular commercial category. Roots songwriters want to be free to forge new directions, blurring and breaking musical limits. On the other hand, musicians are deeply grateful to the giants from whom they learn.