The first act of the Republic was to sweep away the Castle of Porta Giovia, stronghold and symbol of hated tyranny. The people exulted to see it fall, but many thoughtful men, remembering the predatories who coveted the rich city, were dismayed. Nor did the new Constitution prosper. The Milanese had lost all capacity for self-government under the long-continued despotism of the Visconti. ‘Nothing could make Milan free,’ pronounced Macchiavelli later, ‘being altogether corrupt, as was seen after the death of Filippo Visconte, when desiring to establish liberty she neither was able, nor knew how, to maintain it.’ The tyranny of hostile factions triumphed over the best intentions of the Republicans, and the thoughtless people arrayed themselves one against another, behind leaders whose only aim was to subjugate them. Those who had really pure motives were drawn hopelessly into the whirlpool, and the Defenders of Liberty oppressed each other, and the citizens generally, with every cruelty and injustice. Meanwhile the Duchy was claimed by the Guelf party for Alfonso of Aragon, on the strength of a will which his supporters had extracted from the dying Filippo. A pretension—first threat of the misfortune that was to fall later on Milan—was also advanced by the Duke of Orleans, son of Filippo’s sister, Valentina Visconte. The Emperor claimed the Duchy as a vacant fief. More dangerous than any of these pretenders was Venice, greedy to extend her empire. But strongest of all was the resolution of Francesco Sforza, who mended the flaw of illegitimacy in his wife’s claim by the strength of his good sword. General of the Milanese armies at Filippo’s death, he used his power to defend the State from the attacks of Venice, and to subdue it gradually to his own sway. But his enemies were strong. The Piccinini, Francesco and Jacopo, warred against him with arms and intrigue, in alliance with the old Guelf faction. They held Milan against him, but their councils were confused by passion and divisions, and the great general drew steadily nearer to the city. He defeated the Piccinini in the field, and outwitted their perfidious diplomacy with an equal craft. He leagued with Venice and Florence against the new Republic, defeated the Duke of Savoy, whom Filippo’s widow, Maria of Savoy, had enlisted against him, and cutting Milan off from all friends or help, laid siege to the capital itself.