Roman Catholic Diocese of Bergamo in the context of "Ambrosian Rite"

The Ambrosian Rite (Italian: Rito Ambrosiano) is a Latin liturgical rite of the Catholic Church and the Eastern Orthodox Church (specifically The Divine Liturgy of Saint Ambrose). The rite is named after Saint Ambrose, a bishop of Milan in the fourth century. It is used by around five million Catholics in the greater part of the Archdiocese of Milan (excluding Monza, Treviglio and Trezzo sull'Adda), in some parishes of the Diocese of Como, Bergamo, Novara, Lodi, in the Diocese of Lugano, Canton of Ticino, Switzerland, less prominently in some Western Rite orthodox parishes and on special occasions of other jurisdictions.

The Ambrosian Rite has risked suppression at various points in its history. It was reformed after the Second Vatican Council (Pope Paul VI belonged to the Ambrosian Rite, having previously been Archbishop of Milan). In the 20th century, it also gained prominence and prestige from the attentions of two other scholarly Archbishops of Milan: Achille Ratti, later Pope Pius XI, and the Blessed Ildefonso Schuster, both of whom were involved in studies and publications on the rite.