The libretto was complete before his visit to London in 1877.
His Leonore (1798) formed the basis of the libretto of the Fidelio of Beethoven.
Wagner's choice of subjects had from the outset shown an imagination far above that of any earlier librettist; yet he had begun with stories which could attract ordinary minds, as he dismally realized when the libretto of Der fliegende Hollander so pleased the Parisian wire-pullers that it was promptly set to music by one of their friends.
Bernstein also famously conducted an orchestra made up of music students at the festival for the world premier of the opera Peter Grimes, composed by Benjamin Britten with libretto by Montagu Slater.
Accepting this, he remained actively employed until 1839, when he made his first visit to Paris, taking with him an unfinished opera based on Bulwer Lytton's Rienzi, and, like his earlier attempts, on his own libretto.