Badass Baldassare

Angelo Roncalli was elected pope in 1958, and by choosing the name John XXIII probably irritated the gentleman above who had the same appelation, and now rests in the Baptistery in Florence inside a lovely tomb inscribed, "John the former pope." With all those Johns, some confusion has set in.  It began back in the 10th century when there were two John XIVs, and, two hundred years later, no John XX.  There may well have been a female pope named Joan, but that's a tale for another time.  All this sort of skews the infallibility thing, it seems.
Our forgotten first to be the twenty-third of his name had a beginning that was consistent with his end:  born to a noble family who alleviated their impoverishment by becoming pirates, he was ambitious, larcenous and quite successful as a soldier. But he was more the Godfather than a saint.  Baldassare Cossa had risen high enough in the Church hierarchy to be one of the three claimants to the papacy in 1409, and with the death of one, moved into the job, making his fortune quickly by naming the Medicis the Vatican bank on one hand and selling indulgences all over Christendom on the other.
His rivals, Benedict XIII and Gregory XII, didn't go away quietly and had sufficient support to have a Council called at Constance, Switzerland to resolve the dispute.  Always the operator, Cossa tried to distract the gathering by luring the Bohemian "heretic" Jan Hus to state his case there, guaranteeing his safety ("not a hair on his head shall be touched").  Poor Jan, denied any chance to speak, was thrown into a refuse-pit cell for a year, then burned alive (at least we only get pepper spray -- so far -- today).  The sideshow did not work as planned, as Cossa was charged with several heinous crimes and deposed in 1415. Then our former pirate and pope was removed from the official list; no one wanted to share his name for quite some time.  Cossa was imprisoned like his victim, but the Medicis repaid  favors by ransoming him and providing the fine final resting place a few years later.
They don't make 'em like that any more.