Despite their name, the Harlem Hamfats were not from Harlem, but were based in Chicago, and were put together by record producer and entrepreneur J. Mayo Williams simply for the purpose of making records, perhaps the first group to be so created. None of the members of the band were actually from New York. Kansas Joe McCoy (guitar, vocals) and his brother Papa Charlie McCoy (guitar, mandolin) were from Mississippi; Herb Morand (trumpet, vocals), John Lindsay (bass), and Odell Rand (clarinet) were from New Orleans; Horace Malcolm (piano), Freddie Flynn (drums) and Pearlis Williams (drums) were from Chicago. The diverse geographical backgrounds of the musicians played a strong role in the band's sound, which blended blues, dixieland and swing jazz.
Led by Morand and Joe McCoy, the main songwriters, the group initially provided instrumental backing to Williams' stable of artists, including Frankie Half Pint Jaxon, Rosetta Howard, and Johnny Temple. They were perhaps the first example of a studio recording band becoming an act in their own right and recorded extensively. Their first major hits were Oh! Red recorded in April 1936, and Let's Get Drunk And Truck (originally recorded by Tampa Red), recorded in August of the same year. Oh! Red was popular enough to be covered by Count Basie, The Ink Spots, Blind Willie McTell and, later, Howlin' Wolf.