Tratto da:
Il Castello di Milano

Castle of Milan
Period of the Viscontis
Di Baio Editore

1392
Gian Galeazzo, who had already begun to fortify the Castle, now builds a stronghold around it for quartering the soldiers paid to defend his own house placed, it seems, in the stronghhold itself.
1402 Gian Galeazzo dies of the plague in Melegnano after having been proclaimed Duke of Milan and having conquered a great part of Italy. It appears that he dreamed of ruling the whole of the country and becoming a king. His son Giovanni Maria, not yet of age, succeeds him under the guardian of his mother Caterina. Quarrels soon break out, and she takes refuge with her son in the Castle, defended by Jacopo dal Verme.
1404 The Duchess’ enemies demolish the stronghold of Porta Vercellina. The young and dissolute Duke fortifies still more the Castle and names Giovanni Magatti general superintendent for the work.
1412 Giovanni Maria is killed on the threshold of the church of San Gottardo near the Duomo by conspirators among whom are the nobles Ambrogio Tnvulzio Luchino del Maino and others. His younger brother Filippo Maria assures himself the succession by the aid of Marliano, wardour of the castle, who successfully resists the armed assault of a faction of citizens. Filippo Maria chooses the Castle as his residence and has it fortified by Brunelleschi.
1447 Filippo Maria, who had become blind, dies without direct legitimate heirs, leaving only an illegitimate daughter, Bianca Maria.
The Milanese proclaim themselves free, and establish the Aurea Repubblica di Sant’Ambrogio. They occupy the Castle, bought over from the garrison, and begin its
demolition which is continued till 1450.