Modern classical music is music written in the 20th century and beyond. Although much of it draws heavily on earlier forms, modern composers also experimented with rejection of long-held ideas; notably, Arnold Schoenberg questioned the traditional notions of harmony with his twelve-tone system[?], and John Cage questioned the very definition of music with his use of chance and found sounds.
... Suleiman against Charles. While Francis was persuaded to sign a peace treaty in 1538, he again allied himself with the Ottomans in 1542. In 1543 Charles allied himself ...