As the 1920s celebrated the birth of the machine age, American composers were surprised to find that Europe was looking to them as the key to the future of music. There was so much money floating around that commissions were numerous, and composers tried to out do each other in modernist innovations. The age was summed up by George Antheil's "Ballet Mecanique," written "like a solid shaft of steel," with its worship of the machine, its decadent excess of airplane propellers, and 16 player pianos.

In this heady milieu, composers were caught completely off guard by the Great Depression. A turn toward leftist politics began to demand simple music for the proletariat. The most public and successful turnaround came from Aaron Copland, who simplified his style away from dissonance and jazz rhythms toward quotation of folk song; "I wanted to see if I couldn't say what I had to say," he wrote later, "in the simplest possible terms." Quotation of folk songs became de rigueur in the 1930's, brought to a populist climax in Virgil Thomson's works such as "The River" and "The Plow that Broke the Plains." "American Mavericks" is a thirteen episode series on American composers who broke with European tradition to innovate a pure sound. The series won a Peabody Award in 2003.