In the early twentieth century many composers, including Rachmaninoff, Richard Strauss, Giacomo Puccini, and Edward Elgar, continued to work in forms and in a musical language that derived from the nineteenth century. However, modernism in music became increasingly prominent and important; among the most important modernist precursors were Alexander Skryabin, Claude Debussy, and the post-Wagnerian composers such as Gustav Mahler and Richard Strauss, who experimented with form, tonality and orchestration.
Busoni, Stravinsky, Schoenberg, and Schreker were already recognized before 1914 as modernists, and Ives was retrospectively also included in this category for his challenges to the uses of tonality.
Others such as Francis Poulenc and the group of composers known as Les Six wrote music in opposition to the heavy German Romanticism of Wagner and Richard Strauss and the chromaticism and lush orchestration of Claude Debussy.
Composers such as Ravel, Milhaud, and Gershwin combined classical and jazz idioms.
Others, such as Prokofiev, Hindemith, Shostakovich, and Villa-Lobos expanded the romantic palette to include more dissonant elements.
Late-Romantic nationalism was found also in British, American, and Latin-American music of the early twentieth century. Composers such as Ralph Vaughan Williams, Aaron Copland, Carlos Chávez, and Heitor Villa-Lobos used folk themes collected by themselves or others in many of their major compositions.
Many composers sought to break from traditional performance rituals by incorporating theater and multimedia into their compositions, going beyond sound itself to achieve their artistic goals.
Some composers were quick to adopt developing electronic technology. As early as the 1930s, composers such as Olivier Messiaen incorporated electronic instruments into live performance. Recording technology was used to produce art music, as well. The musique concrète of the late 1940s and 1950s was produced by editing together natural and industrial sounds. Steve Reich created music by manipulating tape recordings of people speaking, and later went on to compose process music for traditional instruments based on such recordings.
Other notable pioneers of electronic music include Edgard Varèse, Karlheinz Stockhausen, Pierre Boulez, Luigi Nono, and Milton Babbitt. As more electronic technology matured, so did the music. Late in the century, the personal computer began to be used to create art music. In one common technique, a microphone is used to record live music, and a progrm processes the music in real time and generates another layer of sound. Pieces have also been written algorithmically based on the analysis of large data sets.
Minimlism, involving a simplification of materials and intensive repetition of motives began in the late 1950s with the composers Terry Riley, Steve Reich, and Philip Glass. Later, minimalism was adapted to a more traditional symphonic setting by composers including Reich, Glass, and John Adams. Minimalism was practiced heavily throughout the latter half of the century and has carried over into the 21st century, as well as composers like Arvo Pärt, Henryk Górecki and John Tavener working in the holy minimalism variant.
