The current edifice rises over a pre-existing 5th century Palaeo-Christian church entitled to Sts.
Peter and Paul, built by order of St. Amantius of Como, third bishop of the city.
Erected c. 1 km outside the city's walls, it was intended to house several relics of the two saints which Amantius had brought from Rome.
The structures of the Palaeo-Christian church, discovered in 1863 during a restoration, are still marked by black and pale marble stones in the pavement.
The church has two notable bell towers rising at the end of the external aisles, in the middle of the nave.