Colleoni was born at Solza, in the countryside of Bergamo (Lombardy), where he prepared his magnificent mortuary chapel, the Cappella Colleoni, in a shrine that he seized when it was refused him by the local confraternity, the Consiglio della Misericordia. The family was a noble one, exiled with the rest of the Guelphs by the Visconti. Bartolomeo's father Paolo seized the castle of Trezzo by wile and held it by force, until he was assassinated by his cousins, probably acting on order of Filippo Maria Visconti, duke of Milan. The young Colleoni trained at first in the retinue of Filippo d'Arcello, the new master of Piacenza. Then he entered the service of various condottieri, beginning with Braccio da Montone, who was skirmishing in Apulia, profiting from the struggles between Alfonso of Aragon and Louis of Anjou during the weak sovereignty of Queen Joanna by taking Alfonso's cause, and then of Carmagnola. After the latter was put to death at Venice (1432), Colleoni passed to direct service of the Venetian republic, entering on the major phase of his career. Although Gianfrancesco Gonzaga was namely commander-in-chief, Colleoni was in fact the true leader of the army. He recaptured many towns and districts for Venice from the Milanese, and when Gonzaga went over to the enemy, Colleoni continued to serve the Venetians under Erasmo da Narni (known as Gattamelata) and Francesco Sforza, winning battles at Brescia, Verona, and on the lake of Garda. When peace was made between Milan and Venice in 1441, Colleoni went over to the Milanese, together with Sforza in 1443. Although well treated at first, Colleoni soon fell under the suspicion of the treacherous Visconti and was imprisoned at Monza, where he remained until the duke's death in 1447. Milan then fell under the lordship of Sforza, whom Colleoni served for a time, but in 1448 he took leave of Sforza and returned to the Venetians. Disgusted at not having been elected captain-general, he went over to Sforza once more, but Venice could not do without him; by offering him increased emoluments, Venice induced him to return, and in 1455 he was appointed captain-general of the republic for life. Although he occasionally fought on his own account, when Venice was at peace, he remained at the disposal of the republic in time of war until his death. Colleoni was perhaps the most respectable of all the Italian condottieri. Although he often changed sides, no act of treachery is imputed to him, nor did he subject the territories he passed through to the rapine and exactions practiced by other soldiers of fortune. When not fighting, he devoted his time to introducing agricultural improvements on the vast estates with which the Venetians had endowed him, and to charitable works. At his death in 1475, he left a large sum to the republic for the Turkish war, with a request that an equestrian statue of himself should be erected in the Piazza San Marco. The statue was made by Verrocchio: however, as no monument was permitted in the famous Piazza, it was placed opposite the Hospital of St. Mark.