German-born conductor, who became a US citizen in 1937 and an Israeli citizen in 1970. A legendary figure in his own lifetime, he was renowned for his strict observance of the composer's intentions.
Klemperer grew up in Hamburg and at the age of sixteen entered the Hoch Conservatory in Frankfurt; he later studied in Berlin, specializing in composition, under Hans Erich Pfitzner (1869–1949) and piano. Deeply influenced by Mahler's music, he met the composer in Berlin in 1905 and they became close friends; on Mahler's recommendation Klemperer was appointed conductor of the German Opera in Prague, making his debut there in 1907 conducting Weber's Der Freischütz. Klemperer was then successively conductor at the Municipal Theatre in Hamburg (1910–14), the Strasbourg Opera (1914–17), the Cologne Opera (1917–24), and the State Opera, Wiesbaden (1924–27). By the time he took over the musical directorship of the Kroll Theatre, Berlin, in 1927, he had an extremely high reputation for the classical opera and concert repertoire. He was also known for his eagerness to present contemporary works; at the Kroll Opera he introduced such works as Janáček's From the House of the Dead, Schoenberg's Erwartung and Die glückliche Hand, Stravinsky's The Soldier's Tale and Oedipus Rex, and Hindemith's Cardillac and Neues vom Tage.
Increasingly conservative opposition to his methods, however, led to the closing of the theatre in 1931. Moreover, as a Jew, Klemperer was persona non grata in Germany in the 1930s. When his contract with the Berlin State Opera was summarily cancelled in 1933, he left Gemany to become the director of the Los Angeles Symphony Orchestra. After the war he returned to Europe to conduct the Budapest Opera (1947–50). Despite a series of accidents and operations that left him partially paralysed, he continued to be very much in demand as a conductor. In the 1950s, for example, under the auspices of Walter Legge, he made a series of recordings in London with the Philharmonia Orchestra, including the highly acclaimed Beethoven cycles.