Cosimo arrived back in Florence on 4 September 1433. That afternoon he went to the Palazzo della Signoria to see the Gonfaloniere, Bernardo Guadagni, who was evasive and uncommunicative: the ‘important decisions’ which had necessitated Cosimo’s return from the Mugello would be discussed when the Signoria met in council three days later; in the meantime there was no way of accounting for the rumours of impending trouble which had been circulating in the city for the past few days.
After leaving the Gonfaloniere, Cosimo went to sec one of the Priori whom he believed to be a friend and from whom he received the same kind of vague reassurance. He then went to his bank, no doubt to arrange for the transfer of further sums from Florence. After that he could do nothing but await the imminent meeting of the Signoria.
When he arrived at the Palazzo della Signoria on the morning of 7 September the session had already begun. As the captain of the guard escorted him up the stairs, he passed the shut door of the Council Chamber. Soon after being locked inside his little cell he was told that he had been ‘arrested on good grounds, as would be soon made clear’.
Two days later, on 9 September, the huge Vacca boomed in the belfry above his head to call the citizens of Florence to a Parlamento in the Piazza. As the low, mooing notes of the bell sounded through the city, crowds of people began to converge upon the Piazza in response to its summons; but armed supporters of the Albizzi halted them at the entrances to the square and all those who were known to be, or suspected of being, Medici adherents were denied entry. Looking down from the window of his cell, Cosimo afterwards claimed to have counted no more than twenty-three heads in front of the ringhiera, the ground-floor stone terrace upon which the Priori were standing. In the name of the Signoria these few citizens were asked by the Notaio delle Riformagioni if they agreed to the establishment of a Balìa, a committee of two hundred members ‘to reform the city for the good of the people’. Obediently they gave their approval and a Balìa was accordingly appointed.
Although Rinaldo degli Albizzi now seemed to be in full control of the government, the Balìa could not be persuaded to recommend the execution of Cosimo as he strongly urged it to do. Its discussions were apparently stormy and indecisive, some members supporting the proposal that Cosimo should be beheaded, others arguing that banishment would be punishment enough, one or two suggesting that the prisoner ought to be released. It was clear that many members of the Balìa were reluctant to go to the extremes advocated by the Albizzi not only for fear of the violent disapproval of those thousands of Florentines who, though for the moment intimidated, still looked to the Medici as their champions, but also because his arrest had already called forth strong protests from abroad. The Marquis of Ferrara, a customer of the Medici bank, had intervened on Cosimo’s behalf. The Venetian Republic, also financially indebted to him, had immediately dispatched three ambassadors to Florence who did all in their power to secure his release; and if, after a heated talk with Rinaldo, they failed to do so, their arrival in Florence, as Cosimo said himself, had ‘a great effect on those who were in favour of executing’ him. Rinaldo also had a visit from Cosimo’s old friend, Ambrogio Traversari, Vicar-General of the Camaldolite Order, and supposedly the representative of an even more influential customer of the Medici bank, Eugenius IV, the austere son of a Venetian merchant, who had succeeded Martin V as Pope two years before. By this time Rinaldo had succeeded in bringing a charge of treason against Cosimo by having two of his supporters tortured on the rack. One of these, Niccolò Tinucci, a celebrated notary and occasional poet, had been forced by the city rackmaster to confess that Cosimo had intended to enlist foreign help in bringing about a revolution in the city. Neither Traversari nor the Venetian ambassadors believed in this confession; nor did most of the citizens of Florence. Rinaldo, indeed, was gradually being forced to conclude that he would have to be content with a sentence of banishment rather than the death penalty which his henchman Francesco Filelfo was so insistently demanding.
In his cell in the tower of the Palazzo della Signoria, Cosimo had been allowed to see a few selected visitors, in addition to Ambrogio Traversari. He had also been permitted to have his meals brought over from the Palazzo Bardi as he was afraid of being poisoned. But the greatest care was taken to ensure that he neither received nor gave any messages, and that no communications passed between him and his bank: an official watched over the cooking, carrying and serving of his food, while a guard remained within earshot when he was talking to his visitors. But the guard, Federigo Malavolti, was sympa-pathetic: messages did pass out of the cell, and bribes were offered and accepted. The Gonfaloniere himself, the impecunious Bernardo Gua-dagni, readily pocketed a thousand florins as soon as they were offered to him – he was a feeble fellow, Cosimo afterwards commented derisively, as he could have had ten thousand or more if he had asked for them. Anyway, in return for the relatively modest bribe, Gua-dagni announced that he had suddenly been taken so ill that he could no longer participate in the council’s deliberations; he delegated his vote to another Priore, Mariotto Baldovinetti, who, equally impecunious, had also received a bribe from the Medici coffers.
As well as having to contend with former supporters who had now been suborned, with powerful foreign customers of the Medici bank, with faithful friends of the Medici family who were growing more outspoken every day, and with the gradual desertion of such influential moderates as Palla Strozzi, the Albizzi had also to face the possibility of an armed uprising. For as soon as he heard of the arrest, Cosimo’s brother, Lorenzo, and various other members of the family had rushed out to the Mugello to raise troops to release him. At the same time preparations had been made to assemble a small army of Medici adherents at Cafaggiolo; and the condottiere, Niccolò da Tolen-tino, believed to have received money through Cosimo’s friend, Neri Capponi, had moved down with a band of mercenaries from Pisa to Lastra. Niccolò da Tolentino remained at Lastra for fear that his further advance would result in a tumult in Florence during which Cosimo might be assassinated; but there could be no doubt that he played an important part in Rinaldo degli Albizzi’s ultimate decision to abandon hope of having his tiresome prisoner condemned to death.
On 28 September it was decided that Cosimo should be banished for ten years to Padua, that his wily cousin, Averardo, should be sent to Naples, also for ten years, and that his brother, Lorenzo, a quieter and less offensive figure, should be exiled for five years to Venice. All of them, together with the rest of the family, excepting only the Vieri branch, were declared to be Grandi and thus excluded from office in Florence for ever. Subsequently the leaders of their party in Florence, Puccio and Giovanni Pucci, were banished to Aquila for ten years;6 while the two Priori who had not followed the Albizzi line during the meetings of the Signoria were denied the rewards, in the way of sinecures and appointments of both profit and honour, that were given to all the rest.
When Cosimo, whose many virtues seem not to have included physical courage, was summoned before the Signoria to hear the decree of banishment read out to him, he evidently made a rather abject reply. He protested that he had never frequented the Palazzo della Signoria except when summoned, that he had ‘always declined to be nominated an official’, that far from inciting any Tuscan city to rebel against the government of Florence he had helped to buy several by providing loans to raise troops to conquer them. However, he declared,