This Visconti was widely believed to be mad and was certainly unbalanced. He had been known on summer days to strip the rich clothes from his grotesquely fat and dirty body and to roll about naked in his garden. So ugly that he refused to have his portrait painted, so weak on his deformed legs that he could not rise from his chair without leaning on a page; so nervous that he had been known to scream at the sight of a naked sword; so frightened of thunder that he had a sound-proof room built in his palace; so fond of practical jokes that he would suddenly produce a snake from his sleeve when talking to an unsuspecting courtier, he was also wilful, secretive and inordinately suspicious. Nevertheless, he was undeniably an astute politician who, during the thirty-five years of his rule, succeeded in recovering much of the territory in Lombardy which his father had conquered but which had been lost while he was still a boy. His attempts to extend the Duchy southwards into Tuscany were not, however, so successful, despite assurances from the Albizzi and other Florentine exiles that he had merely to appear in force in the territories of the Republic for the people to take up arms against their oppressors, the Medici. His invading forces were defeated in 1437 at the battle of Barga; they were thwarted again in 1438. And in June 1440 one of his most talented condottieri, Niccolò Piccinino, was routed by an army of Florentine mercenaries in a savage battle near Anghiari on the Arno. After this defeat, Piccinino and the remnants of his army marched quickly out of Tuscany, followed by the Albizzi whose hopes of returning to power were finally dashed. Rinaldo degli Albizzi rode dispiritedly off on a pilgrimage to the Holy Land, while the Florentines took possession of large tracts of lands in the mountainous district of the Cesentino, formerly the domain of an anachronistic feudal lord who had misguidedly joined forces with the Milanese.
At the time of his setback at Anghiari, Duke Filippo Maria Visconti was forty-eight. He had been married twice, first to the rich widow of one of his father’s condottieri whom he charged with adultery and had executed, then to a younger woman whom he had locked up after a dog had howled on their wedding night. By neither wife did he have a child; but a mistress bore him a daughter whom he called Bianca. This Bianca had many suitors but none more persistent than Francesco Sforza.
Francesco Sforza, too, was illegitimate. His father, an illiterate peasant from the Romagna whose name was Giacomo Attendolo, had been kidnapped by a gang of adventurers. After the death of their leader he himself had taken command of them, had adopted the name of Sforza and, before being drowned in the Pescara River while trying to save the life of a young page, had led his men into battle in the service of both Naples and the Pope. At the age of twenty-two, in 1424, Francesco had succeeded his father in command of what was by then one of the best trained bands of mercenaries in Italy, and had subsequently shown exceptional military skill in fighting for the Visconti, the Venetians, the Pope and anyone else prepared to pay the high price he demanded for his services. He was an extremely strong, amiable, down-to-earth man, blunt of speech, with a big, honest face and the simple tastes of a man accustomed to the rough life of a camp. Pope Pius II later wrote of him:
He was very tall and bore himself with great dignity. His expression was serious, his way of speaking quiet, his manner gracious, his character in general such as became a prince. He appeared the only man of our time whom Fortune loved. He had great physical and intellectual gifts. He married a lady of great beauty, rank and virtue by whom he had a family of very handsome children [eight in all, as well as eleven illegitimate children]. He was rarely ill. There was nothing he greatly desired which he did not obtain.
To the annoyance of his occasional employer, the Duke of Milan, he had already carved out a small empire for himself in the Marches; but his ambitions were far from satisfied by that. By marrying Bianca he might, upon her father’s death, succeed to the great Duchy of Milan.
Visconti did not much care for the idea of having this peasant’s bastard as a son-in-law; but Sforza was not only the best soldier in Italy but a political force of consequence. So in November 1441 the Duke at last agreed to the marriage, giving his daughter Pontremoli and Cremona to present to her bridegroom as a dowry and making some rather indeterminate promises about the succession to the Duchy of Milan.
Visconti promises being notoriously unreliable, it came as no surprise when, upon Duke Filippo Maria’s death six years later, it was learned that he had nominated Alfonso, the Aragonese King of Naples, as his heir. Italy was now plunged into uproar. The Duke of Orleans also put forward a claim to the Duchy of Milan as a son of Valentina Visconti. At the same time the German Emperor asserted his ancient rights to Milan; while Venice announced that she would brook no interference in her own claims in Lombardy. As Francesco Sforza prepared to march to take possession of what he considered to be his rightful inheritance, the Milanese – attempting to settle the problem to their own satisfaction – declared themselves masters of their city and re-established their old republic.
In Florence, Cosimo watched the crisis develop with an alert and anxious eye. He had met Francesco Sforza several years before, and had been deeply impressed by his manner and the force of his personality. The friendship then begun had since become more intimate and had been much strengthened by the generous loans which Sforza, in constant financial difficulties, had little difficulty in raising from the Medici bank. As well as lending him money and ensuring that he received additional subsidies from Florentine taxpayers, Cosimo exercised all the political and diplomatic influence he could bring to bear on his behalf. And it was, in fact, largely through Cosimo’s endeavours that Sforza, after three years of warfare and diplomatic negotiations, triumphantly entered Milan as Duke in March 1450.
Cosimo’s unremitting support of Sforza had aroused much angry criticism in Florence, particularly from two of the city’s most prominent citizens, Neri Capponi, who had played an important part in the defeat of Piccinino at Anghiari, and Giannozzo Manetti, the distinguished diplomat. Protests became even more outspoken when, to the extreme annoyance of Naples and Venice, Cosimo recognized Sforza as Lord of Milan before any other state had done so. It was outrageous, so opponents of the Medicean regime maintained, that Florentines should be taxed for the sake of an erstwhile condottiere, now a self-proclaimed duke, the declared enemy of a sister republic which was a traditional ally. Was not Cosimo’s anxiety to back Sforza dictated by fear of losing the huge sums of money he had lent him, and by his expectations of having a more profitable and stable relationship with a despot than he could hope to have with a republic?
Cosimo argued that Venice could no longer be considered a reliable ally: her interests in the Levant clashed with those of Florence; her territorial possessions in the eastern Mediterranean made her an enemy of Turkey with whose empire Florence enjoyed a mutually profitable trade; her shipping was a tiresome rival of Florence’s growing fleet. On the other hand, Milan in the firm grasp of the grateful Sforza would prove an enormously valuable ally both against the encroachments of Venice and in Florence’s still unfulfilled ambition to gain possession of Lucca. Above all, an alliance of Florence with Sforza was the one sure way of bringing peace to Italy, and without peace the commerce of the city could never hope to thrive. Cosimo’s arguments were strongly and ably supported by Nicodemo Tranchedini da Pontremoli, Sforza’s clever and persuasive ambassador in Florence who was to remain there for seventeen years.