Today in Middle Eastern history: the Sixth Crusade ends (1229)

Frederick II successfully concludes perhaps the most unusual of the numbered Crusades.

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It’s probably fair to say that the Fourth Crusade’s sacking of Constantinople is the nadir of the Crusading movement, or the zenith of its absurdity depending on your point of view. In contrast, the Sixth Crusade, while extraordinarily absurd, was at least in technical terms a success. Indeed, 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 captured (or, in this case, successfully bargained for) Jerusalem.

The Sixth Crusade’s success, however is tempered by an amazing number of caveats. For one thing, its leader had been excommunicated, which gives this Crusade the unique distinction of having been actively opposed by the Church. For another thing, it involved barely any actual fighting. It was, instead, a long negotiation between that excommunicated Crusader king—who didn't really want to be on Crusade, didn’t really have much of an army with him, and had no support from the Church—and the feuding leaders of an Ayyubid sultanate that was by this point so decrepit that any value it still placed on possessing Jerusalem was dwarfed by the challenges posed by its own internal crises.

The Sixth Crusade was perhaps the magnum opus for one of the most fascinating figures of Europe’s High Middle Ages: Holy Roman Emperor Frederick II Hohenstaufen (d. 1250). Born in 1194 and son of Emperor Henry VI (d. 1197), he became King of the Romans (by this point the title given to imperial heirs apparent) in 1196 but was obviously too young to stake his claim to the empire upon his father’s unexpected (Henry was only 31) death. The empire fell into a civil war, with Henry’s brother Philip of Swabia (d. 1208) representing to Hohenstaufens and Otto of Brunswick (d. 1218) the rival Welf family. The odd man (well, toddler) out, Frederick was brought south and made King of Sicily (his mother, Constance, was the rightful Sicilian queen by blood).

Sicily had, as regular readers will be aware, been ruled by Arabs from the mid-9th century through the mid-11th century and it was still home to a sizable Arab Muslim population. Frederick, by all accounts a very learned man, thus learned to speak Arabic and was at least familiar with Islam. That familiarity would later raise eyebrows and lead to whispers of heresy, though there’s no indication that Frederick ever viewed himself as anything other than a typical Christian monarch. His own religious proclivities are unclear and he may have even shaded toward the agnostic, but that had no apparent bearing on his public persona.

Both Otto and Philip were elected “king of Germany” by their supporters in the nobility. But only popes could crown emperors, and so the contest between the two was in part about flattering Pope Innocent III (d. 1216). Otto won, in part by offering to go beyond the 1122 Concordat of Worms in allowing popes, rather than emperors, to control the appointment of German bishops and abbots, and in part because Philip refused to give up the Hohenstaufen claim on Sicily and southern Italy. Still the dispute continued, and it wasn’t until Philip was murdered for unclear reasons by Count Otto VIII of Bavaria in 1208 that Innocent finally crowned Otto emperor. Otto and Innocent fell out fairly quickly, though, as Otto’s promises to elevate the papacy over his imperial office evaporated, and Innocent switched his support back to the Hohenstaufens, this time in the person of Frederick, who was crowned King of Germany in 1212 and then emperor in 1220. Otto, in the meantime, suffered a disastrous defeat at French hands in 1214 at the Battle of Bouvines and, under pressure from Frederick, abdicated the following year.

Partly to curry favor with Pope Innocent, Frederick had promised to go on Crusade at his coronation as King of Germany, and he dramatically renewed his pledge when he was crowned emperor in 1220 by Pope Honorius III (d. 1227). This is where things start to go off the rails. Despite those promises, Frederick waffled on joining the 1213-1221 Fifth Crusade, which attacked the Ayyubids in Egypt in an effort to weaken their kingdom and thus leave Jerusalem vulnerable to capture. Throughout that campaign’s long siege of Damietta and the army’s deleterious year of inactivity after finally capturing the city, Frederick kept sending messengers to the Crusaders promising that he was on his way. Some German forces did eventually arrive at Damietta, just in time to join the army’s disastrous march south. But Frederick himself, and the vast army he was supposed to have led, never arrived.

As you might expect, some people took a dim view of Frederick after the Fifth Crusade went bust. Among them was Honorius, who rebuked Frederick for his inaction by letter in 1221. Relations between Frederick and the Vatican weren’t great anyway, but that was the norm between popes and Holy Roman Emperors, who routinely feuded over issues of primacy in the Church. Frederick’s abandonment of the Crusade added a new and powerful grievance to what was already a strained relationship.

Frederick assured that pope that he had wanted to go on Crusade but just hadn't been able to leave Germany, and in his defense he really had been occupied with consolidating his rule over the empire. He promised to lead a great new Crusade that would leave in 1225, ten years after he’d first pledged to take up the cross. Then in 1224, he told Honorius that he was going to need more time to put an army together. To fend off a possible excommunication, Frederick assured Honorius that his Crusade would leave in August 1227, and even signed a document that made it clear he would accept excommunication if he failed to leave at that time.

In the meantime, Frederick had been widowed, and his search for a new bride fell upon Isabella, the daughter of the titular King of Jerusalem, John of Brienne. Since Jerusalem was back in Muslim hands by this point, the “King of Jerusalem” actually ruled from the city of Acre, but the title was more important than the city. John was reluctant to consent to the union, fearing that the much more powerful Frederick would then claim the throne of Jerusalem by marriage. Honorius, on the other hand, loved this idea because he assumed it would commit Frederick to going on Crusade, finally. Frederick denied that he had any interest in claiming the throne, and so John consented, and Frederick and Isabella were married in 1225. Frederick then, and you knew this was coming, claimed the throne of Jerusalem. And there was really nothing John could do about it.

Frederick marrying Isabella and thereby staking his claim to kingship of Jerusalem, from an illustrated manuscript of the 14th century Nuova Cronica by Italian writer Giovanni Villani (Wikimedia Commons)

So by 1227 Frederick was well motivated, both by his pledge and by a desire to legitimize his new kingship, to go on Crusade. It was also a very good time to attempt a new campaign. The Ayyubids were in the midst of a civil war between the sons of the previous sultan, al-Adil (d. 1218), and Frederick was in talks with one of those sons, al-Kamil, about trading Jerusalem for military aid (his Arabic skills and familiarity with Islam made these negotiations possible). And so with the proverbial wind at its proverbial sails (and presumably some actual wind at its actual sails), Frederick’s army set out in August 1227 as promised. It's just that Frederick…wasn’t with it. He’d been stricken by some sort of disease and headed to Naples to recuperate.

The new pope, Gregory IX (d. 1241), was no longer interested in Frederick’s excuses and/or promises, and excommunicated him in late September. This was probably unfair as there’s no question Frederick had been quite ill, but by this point there was a sort of “boy who cried wolf” effect surrounding Frederick and his promises to go on Crusade, and so Gregory seems not to have cared that Frederick’s excuse on this particular occasion was legitimate.

Frederick finally sailed for Acre in May 1228. The Crusade, now led by an excommunicate, was—in technical religious terms—a gigantic mess. Gregory urged Frederick not to go, and then sent letters to Acre warning everyone there that Frederick was not to be obeyed as he was not a legitimate Crusader (nor, at that point, was he a legitimate Christian). He even excommunicated Frederick a second time, I guess in case the first one hadn’t taken or something. Isabella even died shortly before Frederick left, which technically meant he no longer had any claim to be King of Jerusalem. But he went anyway. I said above that Frederick seems to have behaved as a typical Christian monarch, and that’s true, but he clearly saw himself as a Christian ruler in the “direct representative of God” sense, someone who should not be bound by papal authority.

If Frederick’s plans were not affected by his excommunication or the loss of his actual claim to the Jerusalem throne, they were affected by the death of al-Kamil’s main rival for control of the Ayyubid kingdom, his brother al-Muʾazzam. Consequently, the Ayyubids no longer had any incentive to trade Jerusalem for Frederick’s military aid. After arriving in Acre (after yet another lengthy delay in Cyprus hashing out Jerusalem’s political situation) and spending some time wrangling with al-Kamil’s negotiators, Frederick marched his army to Jaffa to rebuild that city's fortifications, which was intended as a threat to al-Kamil. Frederick’s army wasn’t nearly the size it had been when it set out—it seems that when they arrived at Acre without their ruler, most of his men figured that he’d backed out of yet another promise to Crusade and decided to go back home. But this march to Jaffa was impressive enough, apparently, to convince al-Kamil to make a deal.

The deal, which the two men signed on February 18, 1229, was as I said above a technical Crusader victory, but its terms were laughable. Al-Kamil gave Jerusalem to Frederick, but the city had to be kept unfortified, all Muslims living there had to be allowed to remain, and the city’s Muslim holy places would still remain under Muslim control. Given Frederick’s excommunication and his concerns over the terms of the agreement with al-Kamil. the Patriarch of Jerusalem refused to formally crown Frederick King of Jerusalem in the Church of the Holy Sepulcher, and Frederick’s remaining army, largely made up of Knights Templar and Knights Hospitaller, rejected the arrangement as a paper victory.

Frederick made a brief entry into Jerusalem, where he may have crowned himself king (it’s not entirely clear), before returning to Acre, where the patriarch was actually raising his own army to march to Jerusalem and garrison the city properly. This, of course, would have completely wrecked the deal Frederick had cut with al-Kamil, and he therefore put a stop to it. Meanwhile, word reached him that Gregory and John of Brienne were campaigning against his possessions in Italy, so he had to head back to Europe. As a final gift to the Crusaders he was leaving behind, Frederick made sure to destroy all their siege engines, so they wouldn't get any funny ideas about marching on Jerusalem once he’d left. As Frederick rode to the harbor to board his ship home, we’re told that angry townspeople threw garbage at him.

Frederick recovered his Italian holdings, made peace with John and Gregory, and was restored to the Church in the Treaty of Ceprano in 1230. The rest of his life is beyond our scope but is no less fascinating than the tale of his crusade. Gregory excommunicated Frederick again in 1239, when Frederick attacked and defeated the Vatican-allied Lombard League in northern Italy, and went so far as to declare the German ruler a heretic. Frederick spent most of the rest of his life in a literal state of war with the papacy and was actually excommunicated again by Pope Innocent IV in 1245. In a somewhat shocking development, Gregory and Innocent both used crusading terminology to rally other Christian kingdoms against Frederick, ostensibly himself a Christian ruler though officially a heretic as far as the papacy was concerned.

As far as Jerusalem is concerned, the city nominally remained in Christian hands until it was brutally sacked by a Khwarazmian army in 1244 and was recovered and rebuilt by the Ayyubids in 1247. These events led directly to the very unsuccessful Seventh Crusade.