If it’s fair to say that the Fourth Crusade’s sacking of Constantinople discredited the whole enterprise, and in my opinion it is, the Sixth Crusade wrung the last vestiges of seriousness out of the movement. Ironically, of the numbered Crusades it was one of the more successful—certainly more successful than the disastrous Second, Fifth, Seventh, and Eighth Crusades and the…whatever the Fourth Crusade was. An argument could be made that it was the most successful numbered Crusade other than the First, since like the First Crusade it ended with a Christian (well, sort of Christian) ruler having gained control of Jerusalem. That’s how the early Crusaders would’ve defined “success” and by that standard it’s difficult to argue that the Sixth Crusade was a failure, at least on paper.
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additional wrinkle: the Frederick / Gregory dispute went beyond the usual Popes vs. Emperor thing. it had a huge strategic dimension, because Fred was Emperor *and* King of the Two Sicilies. This mean that he literally held the Papal States between his possessions like a nutcracker. It was every Pope’s strategic nightmare, and it meant they all started from a point of being hostile and paranoid towards this guy who had them in a very unnerving strategic encirclement.
it’s true that by the 1220s Imperial domination over Lombardy / northern Italy was pretty nominal. but (1) it wasn’t *completely* nominal — you had Ghibellines (pro-Imperial partisans) in pretty much every city, even if they weren’t actually running things in most of them, and (2) the threat was all too real in Naples / Sicily, where Fred was a pretty dominant centralizing ruler, and Naples / Sicily was all too close to Rome. so Papal strategic concerns may have been exaggerated but they weren’t groundless.
also, let’s note that Gregory IX was a vicious bastard. medieval Popes generally weren’t models of Enlightenment values, but G9 was a full-blast fanatic who rejuvenated the Inquisition, proclaimed the perpetual suppression of the Jews while making literal bonfires of Torahs, aggressively supported the brutal and bloody Northern Crusades, and cracked down hard on dissent of any sort. it would have been hard for any King in Fred’s position to get along with the Papacy, but Gregory was openly hostile pretty much from day one, and was delighted at the chance to excommunicate him.
finally, while the solution was indeed ridiculous, let’s note that it was also one of the very few transfers of power over Jerusalem that was accomplished without any blood being shed or anyone being forced out of the city at sword- or gunpoint. power was shared peacefully and peace was maintained. yeah, it only lasted 15 years. but it’s a rare example of everyone being sensible and choosing a peaceful settlement instead of rolling the dice on war. of course Fred got lambasted for it because it was the fucking 13th century. and, of course,he didn’t go for the peaceful settlement because he was kindly or enlightened. he chose it as the path of least resistance because he was an intelligent man who recognized the whole Crusade business was nonsense on stilts (and insanely expensive nonsense at that), and he wanted to go home. But still!
Doug M.