"The last four years of Alexander’s pontificate were taken up largely with his and Cesare’s ambition to appropriate the Papal States and to turn them into a Borgia family fief. The program was mapped out and put into execution by Cesare, who by now utterly dominated his father. It involved the crushing of many of the great Roman families, above all the Orsini; it necessitated several assassinations, which were normally followed by seizures of property; and it was further financed by the open sale of the highest offices of the Church, including that of cardinal. Cesare Borgia was hated and feared for his violence and cruelty. “Every night,” the Venetian ambassador reported to his government, “four or five men are discovered assassinated, bishops, prelates and others, so that all Rome trembles for fear of being murdered by the duke.”
Yet, although he was hideously disfigured by syphilis - toward the end of his life he never showed himself in public without a mask - few who came in contact with Cesare failed to be impressed. His energy was boundless, his courage absolute. He appeared to need no sleep, and his speed of movement was astonishing: he was said to arrive at one city before he had left the last. At the same time he shared to the full his father's love of women. In his short life - he was to die in battle in Navarre, at the age of thirty-one - he left at least eleven bastards; and the diary of the papal master of ceremonies, Johannes Burchard, leaves us in no doubt of how he spent his leisure:
On Sunday evening, October 30 [1501]. Don Cesare Borgia gave a supper in his apartments in the apostolic palace, with fifty decent prostitutes or courtesans in attendance, who, after the meal, danced with the servants and others there, first fully dressed and then naked. Following the supper, too, lampstands holding lighted candles were placed on the floor and chestnuts strewn about, which the prostitutes, naked and on their hands and knees, had to pick up as they crawled in and out among the lampstands. The Pope, Don Cesare, and Donna Lucrezia were all present to watch. Finally prizes were offered - silken doublets, pairs of shoes, hats, and other garments - for those men who could perform the act most frequently with the prostitutes.
At this point it might be useful to say a word about Donna Lucrezia. She has been cast as the femme fatale of the Borgia dynasty; but to what extent she deserved the role remains uncertain. She was certainly not just a pretty face; on two occasions her father handed over to her the complete control of the Vatican Palace, with authority to deal with his correspondence. As for her reputation, there is absolutely no evidence for the rumors of incest with one or more of her brothers—or indeed with her father—apart from that given by her first husband, Giovanni Sforza, during the divorce proceedings, during which several other baseless accusations were leveled in both directions. She seems to have been very largely the hapless instrument of her father’s and brother’s political ambitions. Her marriage to Sforza in 1493 at the age of thirteen—after two earlier betrothals—was due to Alexander’s eagerness to establish an alliance with Milan; before long, however, the Sforza were no longer necessary and the pope’s son-in-law became an inconvenience. In 1497 there seems to have been a plot to assassinate him—though which of the three Borgias was implicated we shall never know—but he escaped from Rome just in time, and it was then decided that a divorce would be sufficient. Giovanni, who stood to lose not only his wife but also her dowry and the city of Pesaro, which he held in fief from the pope, fought hard but was eventually forced to agree on the humiliating grounds of impotence, despite his testimony that the marriage had been consummated more than a thousand times. There was the additional embarrassment that at the time of the divorce Lucrezia was actually pregnant; but the paternity of the child, Giovanni, who was born in secret, has never been established.
Lucrezia’s next marriage was even more ill starred; her second husband, Alfonso of Aragon, whom she genuinely loved, was murdered by Cesare — quite possibly out of jealousy, though there were also political overtones. She was, we are told, broken-hearted, but her father soon had a third marriage lined up — to another Alfonso, the Este duke of Ferrara. The attendant festivities, on the usual sumptuous scale, were paid for by the sale of eighty new offices in the Curia and the appointment of nine new cardinals — five of them Spaniards — at 130,000 ducats per red hat. (At about the same time the pope also appropriated the entire fortune of the Venetian Cardinal Giovanni Michiel, who had recently died in agony, almost certainly poisoned by Cesare.) This marriage was also ostensibly successful, in that Lucrezia bore her husband a number of children, but it did not prevent her from having passionate affairs with the poet Pietro Bembo and her bisexual brother-in-law, Francesco Gonzaga, Marquis of Mantua. Despite these profligacies, she achieved comparative respectability and outlived the rest of her family, dying in Ferrara in 1519 after giving birth to her eighth child."
--- Absolute Monarchs: A History of the Papacy / John Julius Norwich