No sooner had the presence of the Turks at Otranto, in the extreme southeast of Italy, been rendered a thing of the past by the surrender of the Moslem garrison to the Duke of Calabria in September, 1481, than the peninsula was again ranged in opposing camps by the attempt of the Venetians, assisted by Sixtus and his nephew, to dispossess Ercole d’Este, Duke of Ferrara, of his dominions.  The Duke had married the daughter of Ferdinand, King of Naples, an alliance which, by strengthening him, gave on that account great offence to the Venetians.  They therefore sought to provoke him by insisting on their monopoly of the manufacture of salt in North Italy, and by building a fortress on a part of the Ferrarese territory which they pretended was within the limits of their own.  When he remonstrated, they declined to remove it.  In vain he appealed to Sixtus.  The latter was one of the wolves waiting to devour him.  He then turned to Lorenzo.

To the inexpressible chagrin of Venice and of Sixtus, the Magnifico promptly espoused his cause, formed an alliance with Ferdinand and other states, and, before the Pope and the Venetians were aware he had moved, they found themselves confronted by Naples, Florence, Milan, Bologna, Mantua, and Faenza.  The allies were commanded by Federigo of Montefeltro, Duke of Urbino, while the Venetian-papal troops were placed under Ruberto Malatesta of Rimini.  In this campaign, however, Lorenzo was really the master-spirit.  Although successes were won on both sides, a more than usually tragic complexion was given to the war by the death of the two commanders of the opposing forces.  They had been friends from youth, and such a trifle as the fact that they were hired to fight against each other never disturbed the tenor of their mutual regard.  Armstrong says no more than the truth when he remarks:  “It was a pathetic coincidence.  The two rival generals had bequeathed to each other the care of their children and estates, a characteristic illustration of the easy good-fellowship in this game of Italian war.”

The war dragged on with varying results until Lorenzo played his reserve card.  He induced the Slavic Archbishop of Carniola, who, visiting Rome as the emperor Frederick’s envoy, had been shocked by the shameless immorality of the Pope’s life, to begin an agitation for a general council.  In this he was supported by several of the rulers in Northern Italy and Eastern Europe.  The move was so far successful.  The Pope became alarmed, and hurriedly broke off his alliance with Venice, on the plea that the prevention of fresh schism in the Church must take precedence of every other consideration.  The real fact of the matter was he dreaded the fate of Pope John XXIII, for he knew the actions of his nephew Girolamo Riario would not stand conciliar examination.  Moreover, his other nephew, Giuliano della Rovere, afterward Pope Julius II, a bitter enemy to Girolamo, and Lorenzo’s warm friend, had, during the disgrace of his cousin, gained the Pope’s ear and told him some plain but wholesome truths regarding the unpleasant consequences of a permanent rupture with Lorenzo.