In 1921 he was hired by the Bavarian State Opera in Munich, and then he became Generalmusikdirektor in both Darmstadt (1927) and Hamburg (1931-1933). He gained a reputation for his fine performances of Mozart, Wagner, and Richard Strauss, as well as his championing of modern German music, including operas by Krenek and Berg. Böhm debuted in Vienna in 1933, leading Wagner's Tristan und Isolde. In 1934 he became director of the Dresden State Opera, Richard Strauss's favorite theater. There, Böhm conducted premieres of Strauss's Die schweigsame Frau (1935) and Dafne (1938). He remained at the helm in Dresden through 1943, at which point he became director of the Vienna State Opera (1943-1945). Richard Strauss was not in official favor, and Joseph Goebbels banned any recognition of the great composer's 80th birthday in 1944. However, Böhm participated in a de facto observance, as a large number of Strauss's orchestral and operatic works "just happened" to be played about the time of the birthday.
After the war, Böhm was forbidden to perform until he underwent "de-Nazification," a procedure whereby prominent Austro-Germans were investigated for complicity in Nazi crimes. He was eventually cleared of any suspicion, and was permitted to resume work in 1947.
Böhm oversaw the German repertory at the Teatro Colón in Buenos Aires (1950-1953), and again served as director of the Vienna State Opera (1954-1956). He debuted in the USA at New York's Metropolitan Opera with Mozart's Don Giovanni in 1957, and took prominent German orchestras and opera companies on tour. The Vienna Philharmonic bestowed on him the title "Ehrendirigent," and he was proclaimed Generalmusikdirector of Austria. He left a legacy of many great recordings, including a complete Wagner Ring cycle considered by many critics to be the best. While his Wagner and Strauss were sumptuously Romantic, his Mozart was scrupulously Classical in approach.