Signor, quell'infelice is an aria from Act IV of L'Orfeo, SV 318, an opera written in 1607 by Claudio Monteverdi, with libretto by Aandro Striggio. The opera is based on the Greek legend of Orpheus, and tells the story of his descent to Hades and his fruit attempt to bring his dead bride Eurydice back to the living world. In this particular moment, Proserpina, Queen of Hades, deeply affected by Orpheus singing, begs the King of Hades for Euridice's release. Composed at the point of transition from the Renaissance era to the Baroque, L'Orfeo employs all the resources then known within the art of music, with particularly daring use of polyphony. The work is not orchestrated as such; in the Renaissance tradition instrumentalists followed the composer's general instructions but were given considerable freedom to improvise. This separates Monteverdi's work from the later opera canon, and makes each performance of L'Orfeo a uniquely individual occasion.