There he came under the influence of several popes. Pope Paul II made him Bishop of Savona, but in 1473 he became a cardinal by Pope Sixtus IV, after being supported by the man who became Pope Julius II. When Sixtus IV died (1484), the conclave to elect his successor was chaotic because of two opposing factions. One faction disliked the other so much that they gave their votes to Giovanni Cibo to prevent Cardinal Marco Barbo (a cousin of Paul II) from the papacy. Giovanni Cibo won the next vote and became Pope Innocent VIII.
One of the new pope's first acts was to call a Crusade against the Turks—the Ottoman Empire was expanding rapidly, and had conquered Constantinople a generation earlier. This did not get off the ground due to King Ferdinand I of Naples, mostly due to his own orneriness that led to the 1485 Conspiracy of the Barons, a revolt against Ferdinand's attempt to strengthen his own power at the expense of the feudal hierarchy. Innocent excommunicated Ferdinand in 1489 and asked King of France Charles VIII to come to Italy and take over Naples.
Charles was intrigued, because his paternal grandmother was Marie of Anjou, the eldest daughter of Louis II of Anjou who had been a claimant to the throne of Naples (and ruled part of it from 1390 to 1399). In September 1494 (Innocent had died two years earlier!) Charles invaded with 25,000 men, using gunpowder artillery to march practically unopposed through Pavia, Pisa, Florence, and then Naples. (That, however, is an entirely different story that we might never get to; back to Innocent now.)
Innocent could not get his Crusade against the Turks off the ground, but another opportunity to do something about them came because of Bayezid II, who had become sultan of the Ottomans in 1481. Bayezid was opposed by his brother, Cem, who first tried to get help from the Mamluks of Egypt, and then from the Knights of St. John in Rhodes. Cem made an offer to the Christian world that was very tempting; I'll explain tomorrow.
