The Merry Widow de Franz Lehar, opérette européenne (Allemagne), est l’un des plus grands succès des années 1900 à Londres et à Broadway où elle est la cinquième plus longue série du théâtre musical de la décennie. Sa production à Broadway est la plus influente de son époque et a profondément modifié l'évolution du théâtre musical américain.
Heuberger went to work on the score, but it seems that his heart was never completely in it. Theater An Der Wein's manager, Wilhelm Karczag, was so disappointed when he heard the results that (to Heuberger's relief) he took back the libretto. Karczag wanted to scrap the project until his secretary, Emil Steininger, suggested that they offer the libretto to composer Franz Lehar. The son of a military band master, Lehar had once served as the theatre's orchestra leader and had already worked with Leon & Stein on the hit Der Rastelbinder (1902) and the less successful Der Gottergatte (1904).
Leon openly doubted that the ever-so-Viennese Lehar could invoke Parisian atmosphere. Within hours of receiving the libretto, Lehar presented the producer with the bubbly gallop tune for "Dummer, dummer Reitersmann" -- usually translated as "Silly, silly Cavalier." Supposedly, all reservations were swept aside, even though it is difficult to say what qualified this particular melody as "Parisian." Lehar spent the summer of 1905 working with Leon & Stein, and the score was ready by that fall. After minor delays, the premiere of Die Lustige Witwe was scheduled for late December.