On May 12, 1937, Traubel made her debut appearance on the opera stage, after composer Walter Damrosch asked her to sing the role of Mary Rutledge in the world premiere of his opera "The Man Without a Country" at the Metropolitan Opera.She made her debut with the Chicago City Opera Company later that year, appearing there until the company went bankrupt in 1939. In 1940, she joined the roster of the Chicago Opera Company, remaining a member of that company until it too went bankrupt in 1946. She made her debut with the San Francisco Opera as Brünnhilde in "Die Walküre" on October 9, 1945 with Lauritz Melchior as Siegmund, Margaret Harshaw as Fricka, and William Steinberg conducting; she made several further appearances there during 1945 and 1947.