Cappella Giulia
The Cappella Giulia, officially the Cappella Musicale Giulia della Basilica Papale di San Pietro (English: Julian Cappella of the Papal Basilica of Saint Peter), is the choir of St. Peter's Basilica that sings for all solemn functions of the Vatican Chapter, such as Holy Mass, Lauds, and Vespers, except when these are celebrated by the Pope, when the Sistine Chapel Choir sings instead. The choir has played an important role as an interpreter and a proponent of Gregorian chant and sacred polyphony.