The origin of the Blues as a distinct genre goes back no further than 1890 (at the very earliest). The musical and lyrical elements that have come together in the blues are of diverse and indeterminate origins, but trace pathways that variously stretch across the US and back into Europe and Africa.

Probably, the best book on the subject is David Evans 'Big Road Blues', but also see Giles Oakley 'The Devil's Music' and Paul Oliver 'The Story of the Blues'

Brian