1940s in jazz

Differing greatly from swing, early bebop divorced itself from dance music, establishing itself more as an art form but lessening its potential popular and commercial value.

Kansas City Jazz in the 1930s as exemplified by tenor saxophonist Lester Young marked the transition from big bands to the bebop influence of the 1940s.

These divergences from the jazz mainstream of the time initially met with a divided, sometimes hostile response among fans and fellow musicians, especially established swing players, who bristled at the new harmonic sounds.

The most influential bebop musicians included saxophonist Charlie Parker, pianists Bud Powell and Thelonious Monk, trumpeters Dizzy Gillespie and Clifford Brown, and drummer Max Roach.

Some swing era musicians, like Louis Jordan, later found popularity in a new kind of music, called "rhythm and blues", that would evolve into rock and roll in the 1950s.

By the end of the 1940s, the nervous energy and tension of bebop was replaced with a tendency towards calm and smoothness, with the sounds of cool jazz, which favoured long, linear melodic lines.

The starting point were a series of singles on Capitol Records in 1949 and 1950 of a nonet led by trumpeter Miles Davis, collected and released first on a ten-inch and later a twelve-inch as the Birth of the Cool.