Louis, Rudolf, German writer on music and composer; b. Schwetzingen, Jan. 30, 1870; d. Munich, Nov. 15,1914. He studied philosophy at the Univs. of Geneva and Vienna (Ph.D., 1893), then had instruction from Klose (composition) and Motti (conducting) in Karlsruhe. He was conductor at the theaters in Landshut (1895–96) and in Lübeck (1896–97), and in 1897 settled in Munich, where he became critic for the influential periodical Neueste Nachrichten (from 1900). He wrote a symphonic fantasy, Proteus (1903), as well as pieces for piano, 4-hands, and songs.
Die Weltanschauung Richard Wagners (Leipzig, 1898); Franz Liszt (Berlin, 1900); Hector Berlioz (Leipzig, 1904); Anton Bruckner (Munich and Leipzig, 1904); with L. Thuille, Harmonielehre (1907; 10th ed., 1933; abr. as Grundriss der Harmonielehre, 1908); Die deutsche Musik der Gegenwart (Munich, 1909; 3rd ed., 1912); Aufgaben für den Unterricht in der Harmonielehre (Stuttgart, 1911); Schlüssel für Harmonielehre (Stuttgart, 1912).
—Nicolas Slonimsky/Laura Kuhn/Dennis McIntire