In a strategic position to control traffic through the area, the historiographical tradition associates the events of Angera with the Visconti family and its consolidation after the victory in the Battle of Desio in 1277, celebrated in the frescos of the Sala di Giustizia.
With the Visconti, the Rocca was at the centre of important reconstruction and enlargement works that were to be protracted for more than a century.
In the period of the Ambrosian Republic, the Council of Nine Hundred of the city of Milan ratified the acquisition of Angera, of the fortress and its parish from Vitaliano I Borromeo for the sum of 12,800 imperial lire on 18th January 1449.
