Visconti Milan Succession Crisis

Timeline

1. 1447Milan · MilanThe last Visconti duke Filippo Maria died in Milan without legitimate male heirs, throwing the duchy's legal succession into dispute and forcing the court and citizenry to immediately reorganize power.
2. 1447Milan · MilanThe Milanese civic assembly declared the abolition of the duchy and established the Ambrosian Republic, claiming to reject all foreign lordship and attempting to preserve the duchy's territorial integrity through collective self-rule.
3. 1447–1450Lombardy · LombardyVenice, the Holy Roman Empire, and various mercenary captains intervened in the succession dispute; the Republic first hired then rejected Sforza, and ultimately lost governing capacity through internal division and a prolonged siege, the crisis ending with Sforza's forcible entry into the city.