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Precursors

The great migration of Black Americans to the urban industrial centers of Chicago, Detroit, New York City, Los Angeles, Washington, D.C. and elsewhere in the 1920s and 1930s created a new market for jazz, blues, and related genres of music. These genres of music were often performed by full-time musicians, either working alone or in small groups. The precursors of rhythm and blues came from jazz and blues, which overlapped in the late-1920s and 30s through the work of musicians such as the Harlem Hamfats, with their 1936 hit "Oh Red", as well as Lonnie Johnson, Leroy Carr, Cab Calloway, Count Basie, and T-Bone Walker. There was also increasing emphasis on the electric guitar as a lead instrument, as well as the piano and saxophone.