He found the temporal throne of the Pontiffs tottering when he ascended it. Stefano Porcaro and his distinguished following already in 1453 had attempted the overthrow of the pontifical authority, inspired, no doubt, by the attacks that had been levelled against it by the erudite and daring Lorenzo Valla.
This Valla was the distinguished translator of Homer, Herodotus, and Thucydides, who more than any one of his epoch advanced the movement of Greek and Latin learning, which, whilst it had the effect of arresting the development of Italian literature, enriched Europe by opening up to it the sources of ancient erudition, of philosophy, poetry, and literary taste. Towards the year 1435 he drifted to the court of Alfonso of Aragon, whose secretary he ultimately became. Some years later he attacked the Temporal Power and urged the secularization of the States of the Church. “Ut Papa,” he wrote, “tantum Vicarius Christi sit, et non etiam Coesari.” In his De falso credita et ementita Constantini Donatione, he showed that the decretals of the Donation of Constantine, upon which rests the Pope’s claim to the Pontifical States, was an impudent forgery, that Constantine had never had the power to give, nor had given, Rome to the Popes, and that they had no right to govern there. He backed up this terrible indictment by a round attack upon the clergy, its general corruption and its practices of simony; and as a result he fell into the hands of the Inquisition. There it might have gone very ill with him but that King Alfonso rescued him from the clutches of that dread priestly tribunal.
Meanwhile, he had fired his petard. If a pretext had been wanting to warrant the taking up of arms against the Papacy, that pretext Valla had afforded. Never was the temporal power of the Church in such danger, and ultimately it must inevitably have succumbed but for the coming of so strong and unscrupulous a man as Sixtus IV to stamp out the patrician factions that were heading the hostile movement.
His election, it is generally admitted, was simoniacal; and by simony he raised the funds necessary for his campaign to reestablish and support the papal authority. This simony of his, says Dr. Jacob Burckhardt, “grew to unheard-of proportions, and extended from the appointment of cardinals down to the sale of the smallest benefice.”
Had he employed these means of raising funds for none but the purpose of putting down the assailants of the Pontificate, a measure of justification (political if not ecclesiastical) might be argued in his favour. Unfortunately, having discovered these ready sources of revenue, he continued to exploit them for purposes far less easy to condone.
As a nepotist Sixtus was almost unsurpassed in the history of the Papacy. Four of his nephews and their aggrandizement were the particular objects of his attentions, and two of these—as we have already said—Piero and Girolamo Riario, were universally recognized to be his sons.
Piero, who was a simple friar of twenty-six years of age at the time that his father became Pope, was given the Archbishopric of Florence, made Patriarch of Constantinople, and created Cardinal to the title of San Sisto, with a revenue of 60,000 crowns.
We have it on the word of Cardinal Ammanati(1)—the same gentleman who, with Roderigo de Lanzol y Borja made so scandalously merry in de Bichis’ garden at Siena—that Cardinal Riario’s luxury “exceeded all that had been displayed by our forefathers or that can even be imagined by our descendants”; and Macchiavelli tells us(2) that “although of very low origin and mean rearing, no sooner had he obtained the scarlet hat than he displayed a pride and ambition so vast that the Pontificate seemed too small for him, and he gave a feast in Rome which would have appeared extraordinary even for a king, the expense exceeding 20,000 florins.”
1 In a letter to Francesco Gonzaga.
2 Istorie Florentine.
Knowing so much, it is not difficult to understand that in one year or less he should have dissipated 200,000 florins, and found himself in debt to the extent of a further 60,000.