At the age of 25, Antonio Vivaldi was named master of violin at the Ospedale della Pietà (Devout Hospital of Mercy) in Venice. He composed most of his major works in this position over three decades. The Ospedale was an institution where orphans received instruction -- the boys in trades and the girls in music. The most talented musicians joined an orchestra that played Vivaldi's compositions, including religious choral music. Under Vivaldi's leadership, the orchestra gained international attention. In 1716, he was promoted to music director.
In addition to his choral music and concerti, Vivaldi had begun regularly writing opera scores by 1715; about 50 of these scores remain. His two most successful operatic works, La constanza trionfante and Farnace, were performed in multiple revivals during Vivaldi's lifetime.
- https://www.biography.com/people/antonio-vivaldi-9519560
