The presence of the Church of God in Milan is traced back to the apostolic era.
In the second half of the fourth century, in a period of religious and political tensions, the people were acclaimed bishop Ambrogio, of Roman family, who was in Milan as a consular governor and enjoyed great consensus. With his episcopate (374-397) the Church in Milan took on a metropolitan character.
In historical continuity with this ancient Church - later called "Ambrosian" - the archdiocese of Milan, a local expression of the Roman Catholic Church, has been able to preserve the prerogative of a particular rite over the centuries.
In the nineteenth and above all in the twentieth century the Milanese Church was characterized by the flourishing of many and qualified social, educational, welfare and charitable, cultural and religious initiatives both by individual Christian personalities and by a laity active in various associative forms, both of communities of apostolic life.
The Archdiocese of Milan covers an area of 4,234 square kilometers seven provinces (Milan, Monza, Varese, Lecco, Bergamo, Como and Pavia), up to Campione d'Italia in Switzerland. It is made up of 1,108 parishes distributed in 73 deaneries belonging to 7 pastoral areas (Milan, Varese, Lecco, Rho, Monza, Melegnano, Sesto San Giovanni).