Short answers, pulled from the story.
The first public performance of Dafne occurred in 1597 and was created by Jacopo Peri with a libretto by Ottavio Rinuccini. This work emerged from the Florentine Camerata and fundamentally altered the trajectory of Western music.
Castrati were boys castrated before puberty to preserve high-pitched voices that remained powerful and flexible into adulthood. These singers became the stars of the stage and dominated the operatic world until the early twentieth century, with the last recorded castrato Alessandro Moreschi captured on phonograph recordings.
Jean-Baptiste Lully adapted the Italian model to suit the tastes of Louis XIV by creating the tragédie en musique. This style emphasized ballet, choirs, and a richer orchestra while featuring a French overture with a slow-fast-slow structure and a singing style called déclamation mélodique.
Christoph Willibald Gluck led the reform of opera in the late eighteenth century with works such as Iphigénie en Tauride. His movement emphasized dramatic truth and emotional expression over vocal display and met resistance from traditionalists.
Richard Wagner's concept of the Gesamtkunstwerk sought to unite all the arts into a single creation. This idea combined music, drama, and visual elements to create a unified experience and elevated the status of composers and vocalists during the nineteenth century.