Leon Bismark "Bix" Beiderbecke (March 10, 1903 – August 6, 1931) was an American jazz cornetist, jazz pianist, and composer.
With Louis Armstrong, Beiderbecke was one of the most influential jazz soloists of the 1920s. His turns on "Singin' the Blues" (1927) and "I'm Coming, Virginia" (1927), in particular, demonstrated an unusual purity of tone and a gift for improvisation. With these two recordings, especially, he helped to invent the jazz ballad style and hinted at what, in the 1950s, would become cool jazz. "In a Mist" (1927), one of a handful of his piano compositions but the only one he recorded, mixed classical influences with jazz syncopation. Beiderbecke also has been credited for his influence, directly, on Bing Crosby and, indirectly, via saxophonist Frank Trumbauer, on Lester Young.
Beiderbecke's most influential recordings date from his time with Goldkette and Whiteman, although they were generally recorded under his own name or Trumbauer's. The Whiteman period also marked a precipitous decline in Beiderbecke's health, brought on by the demand of the bandleader's relentless touring and recording schedule in combination with Beiderbecke's persistent alcoholism. A few stints in rehabilitation centers, as well as the support of Whiteman and the Beiderbecke family in Davenport, did not check Beiderbecke's decline in health. He left the Whiteman band in 1930 and the following summer died in his Queens apartment at the age of twenty-eight.