The Theatre in Italy in the 17th century / The opera       The Opera From the musical point of view, Italy in the 16th century closely resembles the rest of Europe and loves a cappella and polyphonic songs. These unaccompanied songs are as appreciated in sacred music as in the profane. With the former, they are particularly employed during mass and with the latter they are part of the “ madrigal structure ”, a type of erudite song issued from popular melodies and Flemish polyphonic influences. Monteverdi is at the time one of the masters of the madrigal and he succeeds in transforming this genre into a musical poem so expressive that he gradually detaches it from the traditional format. It only remains to go one step further for it to become an opera, a step taken by a group of Florentine musicians. This group forms “ La Camarata ” of Count Bardi and comprises artists versed in the theories of Antiquity, as are all humanists of the Renaissance. Notably it includes Vincenzo Galileo, father of the astronomer, and Jacopo Peri. They wish to rediscover the monodic songs of old, using only one voice, in order to purify and to simplify the polyphony of the madrigals and the exuberance of the musical interludes. Their idea consists of producing complete spectacles that include several “ works ”, thus providing the ulterior translation of “ opera ”. In these performances, music, dance, dialogue, costumes and sumptuous decors are combined, while highlighting the isolated voices that stand out from the polyphonic ensemble. Simultaneously the oratorio takes precisely the same path with sacred music. Several spectacles follows this inspiration, and the representation of Dafne in 1597, by Jacomo Peri, followed by his Euridice in 1600 can be identified as the first real attempts at opera. The genre takes on its definitive form with Monteverdi who gives the final touch by creating Orfeo in 1607, since considered as the real birth of the opera as we know it. This is the creation of the lyric drama. Monteverdi transforms the somewhat dry recitative elaborated by the Florentine group, orienting it toward “ the arioso ”, by offering it a transcending melody. Therefore all actors become singers and the music takes a place equal to the song, leaving behind the secondary role to which it was relegated. The Italian of the 17th century then sees a succession of lyric creations in the same mould sometimes taking a more specific form such as the Bel Canto in Naples, whereas the rest of Europe is hardly aware of this new genre. It must be noted that the peninsula, from North to South, has also defined and built specific performance venues that can stage such productions, which for the first time draw a paying public. The operatic theatre thus makes its appearance in Venice and Genoa, cities of trade and finance, and then in the second half of the century it reaches its final format and spreads throughout Italy. These places of festivity and pageant correspond to the aesthetics and exuberance of the baroque as much as to the evolution of society.