Italian composer. Born in the small city of Civita Castellana in northern Latium, wher he received a comprehensive ecclesiastical and musical training at the seminary there. As early as 1622, aged only twenty-five, he was appointed maestro di cappella of Civita Castellana Cathedral; two years later he left his native city for Rome. With the help of his brother Domenico, who had been resident in Rome since 1614, Virgilio quickly penetrated the city's leading musical circles. After brief appointments at the Jesuit Chiesa del Gesù and the Basilica of St John Lateran, in 1629 he was named maestro di cappella of the Cappella Giulia at St Peter's, where he was to remain until his death in 1646. During this period Mazzocchi wrote a large number of works for liturgical use and directed the choir school at St Peter's, but at the same time, as court musician to Cardinal Francesco Barberini, a nephew of Pope Urban VIII., he also composed operas for the extravagant Carnival festivities and took part in oratorio performances and papal academies