Engagements followed at Altenburg, Basel, Cologne (1927–30) and the Berlin State Opera, where he was leading tenor from 1930 to 1944, being especially distinguished in the Italian repertory.
His voice showed little sign of age; it was still warm and sonorous throughout its range, and brilliant and lustrous in its upper register.
He was equally impressive as Andrea Chénier and was also an acclaimed and exciting Radamès and Otello, in which latter role he was often heard on German radio.
Rosvaenge was a prolific recording artist starting as early as 1927, first for the Gramophone Company (now EMI) and later on the Telefunken, Parlophone and Odeon labels.
A recording of his solo tenor singing in a 1938 performance of Verdi's Requiem with the BBC Symphony Orchestra conducted by Arturo Toscanini has been released on CD as well.