1433 Francesco Sforza occupies the March of Ancona, which the pope cedes to him the following year. Peace of Ferrara between Milan and the allies. Treaty between Sigismund and Siena and Florence. Rinaldo degli Albizzi, head of the oligarchy of Florence, imprisons and banishes Cosmo de’ Medici, the leader of the opposition.
1434 The Florentines recall Cosmo de’ Medici and place him at the head of the government. The banished Albizzi flee to Milan and persuade the duke to make war on Florence.
1435 Filippo Maria leagues with Alfonso of Naples against the pope. The Genoese throw off the protection of Milan and restore their independent government.
1436 Renewal of the league between Florence and Venice against Milan. Genoa joins it. Francesco Sforza enters the service of the allies.
1438 Sforza returns to the duke of Milan, who has promised him his daughter in marriage.
1439 The duke of Milan fails to keep his promise and Sforza returns to the allies. He is successful against Milan.
1441 Peace made between Milan and the allies. Sforza marries Filippo Maria’s daughter. Venice acquires the principality of Ravenna.
1443 Pope Eugenius IV plots to wrest the March of Ancona from Sforza. Alfonso of Naples and the duke of Milan aid him. Sforza defeats Piccinino at Monteloro.
1444 Sforza holds out against the alliance, which presses him hard.
1446 Florence and Venice go to the aid of Sforza.