The result is a music diverging widely, even violently, from the previous canons of musical composition, because it is the musical experience of a passing moment, shouting the words with incisive rhythms, and often danced with acrobatic and even grotesque steps. Jazz, with Blues and Country Music, are the precursors of Rock.
Some churches use it in their religious services.
In New Orleans, Louis Armstrong purified it, in form and in content, with beautiful themes of love and majesty, making it more accessible to greater audiences. Gershwin made them classic, with his Rhapsody in Blue. Johnny Cash is a king in this field. Bluegrass is a most joyful music, and here the banjo is the king, with the mandolin and fiddle. It emerged in the United States after World War II, originated by Bill Monroe.