Premiering on January 18, 1947, host Rudi Blesh’s This Is Jazz aired until October 4 of the same year. Blesh was a jazz historian, commentator, and promoter with a special interest in earlier jazz tunes and performers. His first book, Shining Trumpets, was published in 1946, a year before his radio series. This Is Jazz originated from New York’s WOR and was broadcast over the Mutual network as an unsponsored program. The series’ 35 episodes were later released by the Jazzology record label.