 Commentators differ in their views of which of these forms were most important and the degree to which the new music was a re-branding of African-American rhythm and blues for a white market, or a new hybrid of black and white forms.In the 1930s, jazz, and particularly swing, both in urban-based dance bands and blues-influenced country swing (Jimmie Rodgers, Moon Mullican and other similar singers), were among the first music to present African-American sounds for a predominantly white audience.One particularly noteworthy example of a jazz song with recognizably rock and roll elements is Big Joe Turner with pianist Pete Johnson's 1939 single "Roll 'Em Pete", which is regarded as an important precursor of rock and roll.