At a time when many high sopranos offered nothing more than a steam whistle sound, the cool, pure timbre of Erna Berger's instrument fell upon the ears as a balm. Though not large, her instrument had sufficient carrying power to be heard in Europe's largest theaters and not get lost even in the open spaces of the old Metropolitan Opera where she sang briefly beginning in 1949. Trim and petite, she remained a credible stage figure into her fifties and retained to the end of her career the firmness and clarity of tone which had brought her acclaim at an early age. She was an accomplished recitalist and concert singer as well, excelling in the art of German song and such concert works as Beethoven's Ninth Symphony.
Born near Dresden, Berger moved with her family to Paraguay when very young, and was reared there on a farm cleared from the jungle. In her late teens, she worked as a governess to earn funds which would allow her to study voice in Dresden. She trained there with Melizza Hirzel and, in auditioning for a scholarship, was heard by conductor Fritz Busch who engaged her forthwith. Berger made her opera debut at the Dresden Opera in 1925 as the First Boy in Die Zauberflöte. There, she sang numerous roles, many of them in the Italian and French repertories. When she moved on to Berlin, her reputation grew enormously and conductors throughout Europe began to regard her as indispensable for many of the coloratura roles, such as Zerbinetta, the Queen of the Night, and Konstanze.
From 1930 to 1933, Berger was engaged at the Bayreuth Festival, her Shepherd in Tannhäuser and Woodbird in Siegfried being regarded as definitive. The former role is preserved in the legendary Tannhäuser recorded at Bayreuth in 1930 with Maria Müller, Herbert Janssen, and Ivar Andrésen. Her Salzburg debut came in 1932 when she sang Blondchen in Mozart's Die Entführung aus dem Serail; she continued to sing there until 1954 when her Zerlina still appeared and sounded youthful.
On April 30, 1934, she appeared for the first time on a London stage when her Marzelline, described as "enchanting," was heard with Lotte Lehmann, Franz Völker, and Alexander Kipnis. Her Woglinde in Das Rheingold was likewise praised as was her Woodbird. A return engagement was arranged for the following year and, in 1938, Berger was finally available to perform Konstanze (Sir Thomas Beecham has insisted on her). She also sang the Queen of the Night and Sophie in Rosenkavalier. Although her Konstanze was deemed lightweight, it was, according to Francis Toye, "technically first rate." Similar views were expressed about her Queen: well sung, if somewhat lacking the daemonic element. Her Sophie, however, brought no reservations whatever. When Berger returned in 1949, her Queen was more fully appreciated and the public and the critics received both her Sophie and Gilda with unreserved delight.
Rosenkavalier was the opera in which Berger was introduced to the Metropolitan Opera audience on November 21, 1949. Described by Irving Kolodin as "a wonderfully pure, well-phrased Sophie," Berger went on to sing other such specialties as Gilda and the Queen of the Night. From composer/critic Virgil Thomson she won this praise: "She is one of the great sources of musical satisfaction in our time."