German-born US conductor, particularly renowned for his interpretations of Mozart, Mahler, Brahms, and Bruckner.
Having made his debut as a pianist at the age of ten, he studied at the Stern Conservatory, Berlin, and decided to become a conductor after hearing a concert conducted by von Bülow in 1889. In 1894 he made his first appearance as a conductor, in Cologne, and worked at the Hamburg Opera under his close friend Mahler for the first time. In 1901 Mahler engaged him as director of the Vienna State Opera and during the next decade Walter consolidated his European reputation. After Mahler's death in 1911, Walter gave the first performance of Das Lied von der Erde (composed 1908) in Munich, and in 1912 the first performance of Mahler's ninth symphony (1909) in Vienna.
From 1914 to 1922 he was director of the Munich Opera, after which he toured Europe and the USA before returning to Berlin in 1925 as music director of the State Opera and beginning his long association with the Salzburg Festival. In 1929 he became conductor of the Leipzig Gewandhaus Orchestra but suffered antisemitic persecution from the Nazis and left Germany for Austria in 1933. Forced to leave Austria in 1938, following the Anschluss, he moved to France and finally settled in the USA (1939), where he conducted the Metropolitan Opera and the New York Philharmonic (1947–49). After World War II he again performed in Europe, continuing to champion the works of Mahler and also appearing as accompanist with Kathleen Ferrier.