Arnold Schoenberg, Austrian-American composer and painter (born 1874)

Arnold Schoenberg or Schönberg was an Austrian and American composer, music theorist, teacher and writer. He was among the first modernists who transformed the practice of harmony in 20th-century classical music, and a central element of his music was its use of motives as a means of coherence. He propounded concepts like developing variation, the emancipation of the dissonance, and the "unity of musical space".