Venice, prompted by commercial advantage and the threat of Duke Filippo Maria Visconti, who hopes to retake his father’s conquests of Verona and Vicenza and to rule all of northern Italy, allies itself with Florence against Milan in 1426.

Ferrara, Mantua, Siena, and Savoy soon join the Venetian-Florentine alliance and assemble a large army commanded by Francesco Carmagnola.

Upon the entry of Carmagnola’s forces into Brescia in March, 1426, a prearranged revolt breaks out, aiding the imposition of a siege.

Francesco Sforza, the Milanese defender, surrenders, but reinforcements on both sides enable the fighting to continue for eight months, when the last Milanese stronghold falls, with the help of artillery, in November.