Idomeneo is an opera seria with music by Wolfgang Amadeus Mozart. The libretto (words) are in Italian and were written by Giambattista Varesco. He based it on a French text by Antoine Danchet. In 1780 Mozart and Varesco were asked by the Elector of Bavaria to write an opera for a court carnival.
Idomeneo was first performed in Munich on 29 January 1781. Mozart was only 24 years old. It was the first of his great operas.