Così fan tutte o sia La scuola degli amanti Opera buffa ("Dramma giocoso") in 2 Akten

Mozart had a deep and enduring interest in composing music for opera. In the 18^th century, opera belonged to different traditions of which only the Italian opera seria and the Italian opera buffa held wide international appeal. Mozart was commissioned twice to compose an opera seria for the theater in Milan, which was then still under Habsburg rule: Mitridate, re di Ponto, KV 87 (1770); and Lucio Silla, KV 135 (1772). Idomeneo, re di Creta, KV 366 (1781) and La clemenza di Tito, KV 621 (1791) are late examples of opera seria, a genre which gradually declined and was finally abandoned entirely around 1800. Three further works—Ascanio in Alba, KV 111 (1771); Il sogno di Scipione, KV 126 (1771); and Il re pastore, KV 208 (1775)—were so-called “serenatas”, celebratory compositions intended for a single performance at a special occasion.

After 1780, German opera gradually became established in German-speaking countries. In 1781–1782, Die Entführung aus dem Serail, KV 384 originated as part of a short-lived initiative of Emperor Joseph II to promote the German Singspiel (with dialog instead of secco recitatives) at the so-called National-Singspiel. The piece was very popular and was performed throughout the German-speaking world during Mozart’s lifetime. Three opere buffe on librettos by the Viennese court poet Lorenzo da Ponte—Le nozze di Figaro, KV 492 (1786); Don Giovanni, KV 527 (1787); and Così fan tutte, KV 588 (1790)—gained Mozart international acclaim. Die Zauberflöte, KV 620 (1791) was written for a successful suburban theater in Vienna, where Emanuel Schikaneder sought to introduce more serious works into the repertory beyond his usual light comic productions.