By William Landon, Northern Kentucky University
Florence faced a constant problem, referred to as the Pisan problem. Florence had been at frequent war with Pisa since the first quarter of the 15th century. Pisans wanted to maintain their independence and Florence, as a landlocked city, needed Pisa’s port in order to access the Mediterranean for maritime trade.

Failure to Form Citizen Militia at Florence
Having lost Pisa to France in 1494, Florence had seen its economy shrink. And when France had retreated from Italy in 1498, having failed to capture the Neapolitan crown, Pisa was a tantalizing target, and it provided an opportunity for Florence to test its newly instituted citizen militia, which had been constituted in 1506.
Niccolò Machiavelli, who had acted as an ambassador on behalf of the Florentine Republic for several years, had seen first-hand how often mercenary armies were routed by professional state-sponsored armies. He began to press Piero Soderini to form a citizen militia at Florence.
Thus, in 1506, the call to join the militia was published in Florence. What Machiavelli thought would be a grand moment in Florentine republican history turned into a massive flop. To his surprise, the citizens of Florence refused to enlist for training. The appalled Machiavelli, who believed that honor and the desire to protect their homeland would be enough to draw citizens to the militia’s standard, refused to quit chasing his dream.
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Machiavelli’s Trained Citizen Militia
With Soderini’s blessing, Machiavelli traveled to the Mugello (the Medici family’s rural ancestral land) and the Cosentino valley where he impressed its rural denizens into military service.

Machiavelli arranged for 400 trained militia members to drill as part of Florence’s traditional carnival festivities in February of 1506. Machiavelli’s soldiers were disciplined and properly attired; and they displayed a level of seriousness that surprised all of Florence.
The well-trained soldiers he presented to Florence were, in theory, able to defend the city from attack, but, Machiavelli argued, they were also necessary to Florence’s foreign policy.
Three years later, in 1509, Soderini sent Machiavelli and his newly instituted citizen militia, rather than a mercenary army, to Pisa. They laid siege to it, starving the Pisans into submission.
The Medici Join Hands with the Pope
Over the next three years, however, the Medici were steadily gaining power in Rome, and they had the backing of Pope Julius II to support their claims to Florence.
Thus, in 1512, Cardinal Giovanni and Giulio de’ Medici set out from Rome with a Spanish mercenary army. Julius had reformed the Holy League, this time to deal with a resurgent France, and Florence was her ally. Therefore, the pope and the Medici’s interests aligned. If Florence could be taken, the French would be dealt a blow; and if Florence fell, and the Medici were restored, both the pope and the Spanish would be pleased.
Medici’s Plan to Siege Prato
The Medici cardinal did not want to sack his native city. Rather, he hoped that by besieging Florence’s neighboring city—Prato—he might make a statement that would cause Florence to surrender.
Even so, the Florentines had time to plan for the Spanish army’s arrival. The Florentine militia was sent to bolster the defense of Prato. Additionally, the Florentines had sent ambassadors to parley with Cardinal Giovanni de’ Medici and the Spanish viceroy who led their army. These attempts at diplomacy broke down, and the Florentine ambassadors fled for the safety of Florence’s walls.
Destruction of Prato
Like Florence, Prato was a walled city. The Spanish gathered at the Serraglio gate which was located on the northern side of the city, and they began to bombard it with two cannon. As soon as the wall had been breached, the Spanish brought siege ladders to the wall and entered the city. The Florentine militia threw down their weapons and ran without so much as a fight—and they were joined by Prato’s citizenry.
When the Spanish soldiers poured into the city, they went on a rapacious and murderous spree. While it is impossible to know the exact number of casualties that resulted from the massacre—sources range from roughly 2,000 to 6,000 murders and countless rapes and other sacrileges—all of the contemporary chronicles are unanimous in describing the destruction of Prato and its population as horrendous.
According to Francesco Guicciardini (History of Italy), Cardinal Giovanni de’ Medici himself barred the Spanish from sacking Prato’s cathedral, where nuns and maidens had taken refuge. But Machiavelli, who also described the sack of Prato, noted that the numerous churches were sacked and that the virgins who sought refuge inside it were systematically violated and then murdered. The truth of what actually happened within Prato’s walls is hard to discern. But we can conclude that the sack of Prato was horrific.
The Medici Reclaim Florence
The citizens of Prato who were able to escape the city ran to Florence. One can only imagine the scene that greeted Florence’s citizens. They could see Prato smoking on the hill a few short miles from their own walls, and they took in Prato’s bloodied and maimed refugees.
When the Spanish and the Medici turned toward Florence, Machiavelli’s militia stationed on the city’s walls once again threw down their weapons and fled. Piero Soderini waited for the cover of night, and then he, too, fled from Florence—sneaking into a self-imposed exile.
Finally, Cardinal Giovanni reclaimed Florence for the Medici.
Common Questions about Reclaiming of Florence by Cardinal Giovanni de’ Medici
Niccolò Machiavelli, who had acted as an ambassador on behalf of the Florentine Republic for several years, had seen first-hand how often mercenary armies were routed by professional state-sponsored armies. So, he had pressed Piero Soderini to form a citizen militia at Florence.
Machiavelli’s 400 trained militia members were disciplined and properly attired and they displayed a level of seriousness that surprised all of Florence.
The Spanish gathered at the Serraglio gate, which was located on the northern side of Prato, and began to bombard it with two cannon. As soon as the wall had been breached, the Spanish brought siege ladders to the wall and entered the city.