Schüler was born in Vietz, the son of an organist. He studied at the University of Berlin and the Musikhochschule Charlottenburg from 1913 to 1914, and again after the Wold War, in which he served in the military from 1918 to 1920. He studied conducting with Rudolf Krasselt and composition with Paul Juon. In 1920, he began his career as second Kapellmeister at the in Upper Silesia. In 1922 he changed to the, and in 1924 for the first time to the Opernhaus Hannover, where he was Zweiter Kapellmeiser under Krasselt. In 1928 Schüler became Landesmusikdirektor in Oldenburg where he remained for four years. He became noted for his engagement for contemporary music. Thus, during his engagement in Oldenburg in 1928, being one of the first to conduct Alban Berg's Wozzeck. On 14 April 1930, he conducted the world premiere of Berg's Three Pieces for Orchestra, Op. 6, with the Oldenburger Landesorchester. He, along with his predecessor, Werner Ladwig, made Oldenburg a center of contemporary music in Germany. In 1932, Schüler moved to the Halle Opera House. After the Nazis seized power in 1933, he was municipal music director in Essen to 1936, and was appointed to the Berlin State Opera in 1935. In 1937, he joined the Nazi Party and in 1938 was appointed by Hitler as "Staatskapellmeister", and the following year Generalintendant. On 3 October 1943, he performed with the Berlin Philharmonic in occupied Krakow. Schüler conducted the last performance at the Berlin State Opera on 31 August 1944, Mozart's Figaro, before all German theatres were closed because of World War II. Hitler listed him as Gottbegnadet, which saved him from military duties. After the war, he conducted the first Berlin performance of Hindemith's Mathis der Maler at the State Opera in 1948. In 1949, he went to Hanover for the second time, where he was Generalmusikdirektor until 1960. He conducted the world premiere of Henze's Boulevard Solitude on 17 February 1952, staged by Jean-Pierre Ponnelle. He maintained relations to the Berlin State Opera as a regular guest conductor. He conducted Verdi's Rigoletto on 20 September 1945, directed by Wolf Völker. In 1954, he took part in the first guest appearance of the company, to Paris. He conducted in Berlin Tchaikovsky's Eugen Onegin on 4 October 1955, staged by, and Wozzeck on 14 December that year, staged by Werner Kelch with stage design by. Schüler died in Berlin at the age of 72.
