Modernism is a philosophical movement that, along with cultural trends and changes, arose from wide-scale and far-reaching transformations in Western society in the late 19th and early 20th centuries. Among the factors that shaped modernism were the development of modern industrial societies and the rapid growth of cities, followed then by the horror of World War I. Modernism also rejected the certainty of Enlightenment thinking, and many modernists rejected religious belief.
Modernism, in general, includes the activities and creations of those who felt the traditional forms of art, architecture, literature, religious faith, philosophy, social organization, activities of daily life, and even the sciences, were becoming ill-fitted to their tasks and outdated in the new economic, social, and political environment of an emerging fully industrialized world. The poet Ezra Pound's 1934 injunction to "Make it new!" was the touchstone of the movement's approach towards what it saw as the now obsolete culture of the past. In this spirit, its innovations, like the stream-of-consciousness novel, atonal (or pantonal) and twelve-tone music, divisionist painting and abstract art, all had precursors in the 19th century.
In music, modernism is a philosophical and aesthetic stance underlying the period of change and development in musical language that occurred around the turn of the 20th century, a period of diverse reactions in challenging and reinterpreting older categories of music, innovations that lead to new ways of organizing and approaching harmonic, melodic, sonic, and rhythmic aspects of music, and changes in aesthetic worldviews in close relation to the larger identifiable period of modernism in the arts of the time. The operative word most associated with it is "innovation" (Metzer 2009, 3). Its leading feature is a "linguistic plurality", which is to say that no one music genre ever assumed a dominant position (Morgan 1984, 443).
Examples include the celebration of Arnold Schoenberg's rejection of tonality in chromatic post-tonal and twelve-tone works and Igor Stravinsky's move away from metrical rhythm (Campbell 2010, 37).
Musicologist Carl Dahlhaus describes modernism as: