Jazz moved to a new and more intense level of creativity in the forties. Redefined and reassembled by a number of key figures, it entered what critics tightly tied to the past called an “impossible” phase—a stormy adolescence. No longer a charming, entertaining, ingratiating child, the comparatively sophisticated jazz of the forties challenged the listener and musician, motivating a complete reassessment of position.

The decade's changes offered but two options: one either dismissed the “modern” harmonies, melodies, and rhythms and the imaginative, facile players, arrangers, and composers who created this music, negating their need for self assertion and identity, and retreated into the comfort of the past; or one listened— a new experience for some—and came to terms with the times. For a surprising number it was difficult to accept the revolution. Battle lines were drawn. The traditionalists, including several leading musicians —Louis Armstrong was one—and those with contemporary inclinations found little or no common ground.

By its nature an evolving form, jazz had been undergoing modifications through the thirties. The next ten years, however, brought together the right circumstances and gifted, discontented people seeking to offer an accurate musical picture of the period and themselves—the components for rebellion.