The French army was now preparing to cross the Alps a second time, under the
command of Trivulce. Louis XII had come as far as Lyons in the company of
Caesar Borgia and Giuliano della Rovere, on whom he had forced a
reconciliation, and towards the beginning of the month of May had sent his
vanguard before him, soon to be followed by the main body of the army. The
forces he was employing in this second campaign of conquest were 1600 lances,
5000 Swiss, 9000 Gascons, and 3500 infantry, raised from all parts of France.
On the 13th of August this whole body, amounting to nearly 19,000 men, who
were to combine their forces with the Venetians, arrived beneath the walls of
Arezzo, and immediately laid siege to the town.
Ludovico Sforza's position was a terrible one: he was now suffering from his
imprudence in calling the French into Italy; all the allies he had thought he might
count upon were abandoning him at the same moment, either because they were
busy about their own affairs, or because they were afraid of the powerful enemy
that the Duke of Milan had made for himself. Maximilian, who had promised him
a contribution of 400 lances, to make up for not renewing the hostilities with Louis
XII that had been interrupted, had just made a league with the circle of Swabia to
war against the Swiss, whom he had declared rebels against the Empire. The
Florentines, who had engaged to furnish him with 300 men-at-arms and 2000
infantry, if he would help them to retake Pisa, had just retracted their promise
because of Louis XII's threats, and had undertaken to remain neutral. Frederic,
who was holding back his troops for the defence of his own States, because he
supposed, not without reason, that, Milan once conquered, he would again have
to defend Naples, sent him no help, no men, no money, in spite of his promises.
Ludovico Sforza was therefore reduced to his own proper forces.
But as he was a man powerful in arms and clever in artifice, he did not allow
himself to succumb at the first blow, and in all haste fortified Annona, Novarro,
and Alessandria, sent off Cajazzo with troops to that part of the Milanese territory
which borders on the states of Venice, and collected on the Po as many troops
as he could. But these precautions availed him nothing against the impetuous
onslaught of the French, who in a few days had taken Annona, Arezzo, Novarro,
Voghiera, Castelnuovo, Ponte Corona, Tartone, and Alessandria, while Trivulce
was on the march to Milan.
Seeing the rapidity of this conquest and their numerous victories, Ludovico
Sforza, despairing of holding out in his capital, resolved to retire to Germany, with
his children, his brother, Cardinal Ascanio Sforza, and his treasure, which had
been reduced in the course of eight years from 1,500,000 to 200,000 ducats. But
before he went he left Bernardino da Carte in charge of the castle of Milan. In
vain did his friends warn him to distrust this man, in vain did his brother Ascanio
offer to hold the fortress himself, and offer to hold it to the very last; Ludovico
refused to make any change in his arrangements, and started on the 2nd of
September, leaving in the citadel three thousand foot and enough provisions,
ammunition, and money to sustain a siege of several months.