Fidelio work on the libretto by Georg Friedrich Treitschke. This version was first performed at the Kärntnertortheater on 23 May 1814, again under the title "Fidelio". The 17-year-old Franz Schubert was in the audience, having sold his school books to obtain a ticket. The increasingly deaf Beethoven led the performance, "assisted" by Michael Umlauf, who later performed the same task for Beethoven at the premiere of the Ninth Symphony. The role of Pizarro was taken by Johann Michael Vogl, who later became known for his collaborations with Schubert. This version of the opera was a great success, and "Fidelio" has been
Fidelio to be broadcast in the USA, over the NBC radio network, in December 1944, by the NBC Symphony Orchestra, featuring soloists from the Metropolitan Opera (though a shortwave broadcast of one act, conducted by Toscanini, had earlier been relayed from a 16 August 1936 performance at Salzburg.) Divided into two consecutive broadcasts, the 1944 performances were later issued by RCA Victor on LPs and CDs. "Fidelio" was the first opera performed in Berlin after the end of the World War II, with the Deutsche Oper staging it under the baton of Robert Heger at the only undamaged theatre, the Theater