Orfeo ed Euridice is an opera composed by Christoph Willibald Gluck based on the myth of Orpheus, set to a libretto by Ranieri de' Calzabigi. It belongs to the genre of the azione teatrale, meaning an opera on a mythological subject with choruses and dancing. The piece was first performed at Vienna in 1762. Orfeo ed Euridice is the first of Gluck's "reform" operas, in which he attempted to replace the abstruse plots and overly complex music of opera seria with a "noble simplicity" in both the music and the drama.