Given the below context:  (English: "The Marriage of Thetis") After Duke Vincenzo's death in February 1612, Monteverdi found himself out of favour at the Mantuan court. Vincenzo's successor Francesco had no high regard for Monteverdi, and dismissed him from his post. Upon Francesco's sudden death in December 1612, the dukedom passed to his brother Ferdinando, but Monteverdi was not recalled to the court and was appointed maestro di capella in August 1613 at St Mark's, Venice. However, he remained in contact with Striggio and other highly placed Gonzaga courtiers, through whom he was able to secure occasional commissions to compose theatrical works for the Gonzaga court. Thus, late in 1616, Striggio asked him to set to music Scipione Agnelli's libretto Le nozze di Tetide, as part of the celebrations for Duke Ferdinando's forthcoming marriage to Catherine de' Medici. This story, based on the wedding of the mythical Greek hero Peleus to the sea-goddess Thetis, had previously been offered to the Mantuan court by Peri, whose setting of a libretto by Francesco Cini had been rejected in 1608 in favour of L'Arianna.Initially, Monteverdi had little enthusiasm for Le nozze di Tetide, and sought ways of avoiding or delaying work on it. He would accept the commission, he informed Striggio on 9 December 1616, because it was the wish of the duke, his feudal lord. However, the verses he was given were not, he felt, conducive to beautiful music. He found the tale difficult to understand, and did not think he could be inspired by it. In any event he was occupied for most of December in writing a Christmas Eve mass for St Mark's. On 29 December, perhaps hoping that the commission would be withdrawn, Monteverdi told Striggio that he was ready to begin work on Le Nozze di Tetide "if you tell me to do so". In January 1617, however, he became more enthusiastic on learning that the project had been scaled down and was now being projected as a series of intermedi. He informed Striggio that what he had first considered a rather monotonous piece he now thought...  Guess a valid title for it!
A:
Lost operas by Claudio Monteverdi