Bayreuth Festival talented conductor Hermann Levi, who was personally chosen by Richard Wagner to conduct the debut of "Parsifal" in 1882 with the assistance of the young Engelbert Humperdinck. Following Wagner's death, his widow Cosima continued running the festival at one or, more frequently, two-year intervals. She gradually introduced the remaining operas which complete the Bayreuth canon of Wagner's last ten completed operas. Levi, the son of a rabbi, remained the festival's principal conductor for the next two decades. Felix Mottl, who was involved with the festival from 1876 to 1901, conducted "Tristan und Isolde" there in 1886. Until the 1920s, performances
Bayreuth Festival the festival into an opportunity for directors to experiment with new methods for presenting the operas. The change came out of necessity, as it was impossible for Wolfgang to both administer and direct the festival. It also provided an opportunity for Bayreuth to renew itself with each production, rather than continue to present the same operas in the same way, year after year. Ingmar Bergman, who famously made a film version in Swedish of Mozart's "Die Zauberflöte", turned down an invitation to direct the festival. The most sensational production in "Werkstatt Bayreuth" was the Centennial Ring Cycle under the direction