She made her debut as a concert singer with the Saint Louis Symphony Orchestra in 1923, and in 1926 she received an offer to join the Metropolitan Opera company after performing the Liebestod from Wagner's Tristan und Isolde at the Lewisohn Stadium under conductor Rudolph Ganz.

[5] Since the Metropolitan already had two first-class Wagnerian sopranos, Kirsten Flagstad and Marjorie Lawrence, Traubel at first had difficulty finding her niche at the Met.

Her debut as a regular member of the company was as Sieglinde in Die Walküre in 1939, the only standard role which she had previously sung, at the Chicago Opera.

On February 22, 1941, Arturo Toscanini conducted Traubel and tenor Lauritz Melchior in excerpts from Wagnerian operas, including act 1, scene 3 of Die Walküre on the live radio broadcast concert of the NBC Symphony Orchestra.

[6] Traubel's association with the Metropolitan Opera ended in 1953; General Manager Rudolf Bing chose not to renew her contract after expressing disapproval of her radio and TV appearances alongside the likes of Jimmy Durante, and her wish to expand her lucrative career in major supper and night clubs.

[7] After her Met career, she appeared on Broadway in the Rodgers and Hammerstein financial failure, Pipe Dream, playing a bordello madame with a heart of gold and the voice of Isolde.

[10] A full-length follow-up, The Metropolitan Opera Murders (1951), was ghostwritten by Harold Q. Masur[11] and features a soprano heroine, Elsa Vaughan, who helps solve the mystery.

[3]) Traubel died of a heart attack in Santa Monica, California, aged 73, and was interred in the Westwood Village Memorial Park Cemetery in Los Angeles.