About the work
Tragédie en musique in a prologue and five acts by Jean-Baptiste Lully after a libretto by Philippe Quinault, first performed on 5 January 1677 before the court of Louis XIV at the Château de Saint-Germain-en-Laye. It was the fifth joint opera of Lully and Quinault and the first of Lully's scores to be published during his lifetime.
Plot
Jupiter falls in love with the nymph Io and turns her into a white heifer to hide her from his jealous wife Juno. Juno sees through the ruse, has Io watched by the monster Argus and tormented by the infernal spirit Hierax, driving her into an icy wasteland. Only Jupiter's intercession saves her: Io is elevated to the goddess Isis, worshipped in Egypt.
Cultural significance
Contemporaries read Jupiter's shift from Juno to Io as a veiled allusion to Louis XIV's own shift from his mistress Madame de Montespan to her younger rival Madame de Ludres; Montespan is said to have had Quinault banished from court for two years as a result. Despite the scandal, musicians admired the opera's refined orchestration, including its feverish, frost-bound chorus set in the icy wastes of Scythia, which earned the work its nickname 'l'opéra des musiciens'.