Fanny Mendelssohn, sister of Felix Mendelssohn, introduced the keyboard music of Johann Sebastian Bach to Gounod, who came to revere him. For him The Well-Tempered Clavier was "the law to pianoforte study...the unquestioned textbook of musical composition". It inspired Gounod to devise a melody and superimpose it on the C major Prelude (BWV 846) from the collection's first book. To this melody in 1859 (after the deaths of both Mendelssohn siblings), Gounod fitted the words of the Ave Maria, resulting in a setting that became world-famous.[6]
Gounod wrote his first opera, Sapho, in 1851 at the urging of his friend, the singer Pauline Viardot; it was a commercial failure. He had no great theatrical success until Faust (1859), derived from Goethe. This remains the composition for which he is best known; and although it took a while to achieve popularity, it became one of the most frequently staged operas of all time, with no fewer than 2,000 performances of the work having occurred by 1975 at the Paris Opéra alone.[7] The romantic and melodious Roméo et Juliette (based on the Shakespeare play Romeo and Juliet), premiered in 1867, is revived now and then but has never come close to matching Faust's popular following. Mireille, first performed in 1864, has been admired by connoisseurs rather than by the general public. The other Gounod operas have fallen into oblivion.