Aside from musical friends and experiences, von Einem's personality was, of course, also affected by the serious developments in Europe. For several years, he had been helping people escape from the totalitarian German state. Somehow, the Gestapo learned of this, and he was arrested and interrogated. The entire story is Kafkaesque, like a scene from von Einem's second opera, a setting of Kafka
's Der Prozess (The Trial, 1953, produced at the Salzburg Festival).
Von Einem was released, and obtained the position of resident composer and musical adviser to the Dresden Staatsoper in 1944, simultaneous with the success of his first stage work, a ballet entitled Prinzessin Turandot (Princess Turandot, in two scenes). Shortly after the war's end, his first opera Dantons Tod (The Death of Danton, 1944 -- 1946) was given at the 1947 Salzburg Festival, securing international fame for the composer. In these first two operas, the von Einem "sound" is clearly heard with its strong jazz-influenced rhythms, its touches of Stravinsky
and Blacher, rich harmonies, powerful string writing, and a sectional organization that avoids traditional continuity.
From 1948 to 1951, von Einem was a board member for the Salzburg Festival, and then chairman of the Kunstrat (Art Advisory). In 1953, he moved to Vienna and was a board member of the Concert House Society, and a director of the Vienna Festival from 1960 to 1964. He composed his third opera, a folk comedy-farce entitled Der Zerissene (The Torn One, 1961 -- 1964), four new ballets including the energetic Pas de coeur (Death and Resurrection of a Ballerina) (1952), a Piano Concerto (1955), an oratorio with words by Brecht Das Stundenlied (The Song of the Hours, 1958), and the orchestral Symphonic Scenes (1956), one of several American commissions. Von Einem was gradually moving away from his early Expressionist atmospheres.
He began teaching composition in 1965. His important works of the 1970s include the operas The Old Lady's Visit, with text by Dürrenmatt (1971); and Cabal and Love (1976); the song cycle Rosa mystica; and the oratorio An die Nach gebornen for the 30th anniversary of the UNO in New York.