The first major phase of avant-garde music took place in Paris and Vienna from around 1890 to 1914. Claude Debussy, Igor Stravinsky (a young Russian working in Paris), and Arnold Schoenberg were the leading figures in this brilliant era. And there were strong modernist rumblings in Russia, Hungary, Italy, and the United States.

It was a period of rapid development in all the arts, as we have seen, in which the basic tenets of nineteenth-century art were everywhere challenged. In music, nineteenth-century ideas of melody, harmony, tonality, rhythm, and tone color came under attack. Above all, it was the revolution in tonality — which went along with a radical reconsideration of melody and harmony — that caught the imagination of the early twentieth century.