March, Cardinal della Rovere, concealing his activities from his principal rival, Cardinal Rodrigo Borgia (later Pope Alexander VI), rode out of Rome and departed by sea from Ostia, intending to head for Genoa and Avignon to prepare to wage war between the Church and the King of Naples, Ferdinand I (Ferrante). On 28 June the Pope sent back to Naples the token gift of a palfrey which symbolized the King of Naples' submission and demanded the full feudal submission of the Kingdom of Naples to the Roman Church according to long-standing tradition. In a second attempt to overthrow the Aragonese monarchy, the Prince of Salerno Antonello II di Sanseverino, on the advice of Antonello Petrucci and Francesco Coppola, gathered together several feudal families belonging to the Guelph faction and supporting the Angevin claim to Naples. Antonello de Sanseverino was the brother-in-law of Cardinal della Rovere's brother Giovanni, who was a noble of Naples because of his fief of Sora. The principal complaints of the barons were the heavy taxation imposed by Ferdinand to finance his war against the Saracens, who had occupied Bari in 1480; and the vigorous efforts of Ferrante to centralize the administrative apparatus of the kingdom, moving it away from a feudal to a bureaucratic system. The barons seized L'Aquila and appealed to the Pope for assistance as their feudal overlord. Genoa and Venice supported the Papacy, while Florence and Milan opted for Naples. In Rome, the Orsini allied themselves with Ferrante's son Alfonso, and therefore the Colonna supported the Pope in the street fighting that ensued. Ferrante reacted by seizing the fiefs of the barons, and, when the two parties met to negotiate a settlement, Ferrante had them arrested, and eventually executed. The prestige of the della Rovere family was seriously damaged, and in an attempt to exculpate himself Pope Innocent began to withdraw his support for them. Peace was restored in 1487, but Innocent VIII's papacy was discredited. Papal ambassador On 23 March 1486, the pope sent Giuliano as Papal Legate to the Court of King Charles VIII of France to ask for help. A French entourage arrived in Rome on 31 May, but immediately relations broke down with the pro-Spanish Cardinal Rodrigo. But Ferrante's army decided the pope's humiliation, Innocent backed down and on 10 August signed a treaty. Innocent looked for new allies and settled on the Republic of Florence. On 2 March