Opera in German such as opera seria. Some Baroque composers, such as Reinhard Keiser, did try to challenge Italian dominance, and the theatre principal Abel Seyler became an eager promoter of German opera in the 1770s, but it was only with the appearance of Mozart that a lasting tradition of serious German-language opera was established. Mozart took the simple, popular genre of "Singspiel" and turned it into something far more sophisticated. Beethoven followed his example with the idealistic "Fidelio"; and with "Der Freischütz" of 1821, Weber established a uniquely German form of opera under the influence of Romanticism. Weber's innovations were eclipsed by
Washington National Opera order of the day". Four months later, the Society staged a double bill of Gian Carlo Menotti's opera "The Old Maid and the Thief" along with his ballet "The Unicorn, The Gorgon, and the Manticore". It was very successful with both the public and critics alike. Successful presentations followed from November 1957 onwards: "Fidelio"; "Ariadne auf Naxos"; "Idomeneo"; a double bill of Schoenberg's "Erwartung" and Stravinsky's "Le Rossignol" (conducted by the composer); and a December 1961 "The Magic Flute" which resulted in an invitation from President John Kennedy at the White House for some excerpts from the opera. By this