engaged the marquis of Mantua; they also as earnestly requested the Venetians to send them Count Carlo, son of Braccio, and Deifobo, son of Count Jacopo, and after many delays, they complied; for having made a truce with the Turks, they had no excuse to justify a refusal, and could not break through the obligation of the League without the utmost disgrace.  The counts, Carlo and Deifobo, came with a good force, and being joined by all that could be spared from the army, which, under the marquis of Ferrara, held in check the duke of Calabria, proceeded toward Pisa, to meet Signor Roberto, who was with his troops near the river Serchio, and who, though he had expressed his intention of awaiting their arrival, withdrew to the camp at Lunigiana, which he had quitted upon coming into the Pisan territory, while Count Carlo recovered all the places that had been taken by the enemy in that district.

The Florentines, being thus relieved from the attack in the direction of Pisa, assembled the whole force between Colle and Santo Geminiano.  But the army, on the arrival of Count Carlo, being composed of Sforzeschi and Bracceschi, their hereditary feuds soon broke forth, and it was thought that if they remained long in company, they would turn their arms against each other.  It was therefore determined, as the smaller evil, to divide them; to send one party, under Count Carlo, into the district of Perugia, and establish the other at Poggibonzi, where they formed a strong encampment in order to prevent the enemy from penetrating the Florentine territory.  By this they also hoped to compel the enemy to divide their forces; for Count Carlo was understood to have many partisans in Perugia, and it was therefore expected, either that he would occupy the place, or that the pope would be compelled to send a large body of men for its defense.  To reduce the pontiff to greater necessity, they ordered Niccolo Vitelli, who had been expelled from Citta di Castello, where his enemy Lorenzo Vitelli commanded, to lead a force against that place, with the view of driving out his adversary and withdrawing it from obedience to the pope.  At the beginning of the campaign, fortune seemed to favor the Florentines; for Count Carlo made rapid advances in the Perugino, and Niccolo Vitelli, though unable to enter Castello, was superior in the field, and plundered the surrounding country without opposition.  The forces also, at Poggibonzi, constantly overran the country up to the walls of Sienna.  These hopes, however, were not realized; for in the first place, Count Carlo died, while in the fullest tide of success; though the consequences of this would have been less detrimental to the Florentines, had not the victory to which it gave occasion, been nullified by the misconduct of others.  The death of the count being known, the forces of the church, which had already assembled in Perugia, conceived hopes of overcoming the Florentines, and encamped upon the lake, within three miles of the enemy.