In 1947 two white bar owners, Leonard and Phil Chess, decided to start their own record label, Aristocrat, specializing in the type of urban blues popular in their clubs. Their first single, by a black singer named Andrew Tibbs, almost wrecked the new label. The A side was "Bilbo's Dead," a tune mocking the recent death of arch-segregationist senator Theodore G. Bilbo. The song was immediately banned in much of the South, Aristotocrat's intended market. To make matters worst, the B side, "Union Man Blues," a song protesting black exclusion from labor unions, so incensed truckers that they refused to ship the record. The Chess brothers, however, would have later luck with less political songs, and their label, Chess, would become famous for records by artists such las Muddy Waters and Chuck Berry.

Source: Francis Davis, The History of the Blues (New York: Hyperion...