The Sistine Chapel

As he had promised the dearly departed Pope Innocent III he would do, King Andrew II of Hungary led a Fifth Crusade to the novel land of Egypt in 1217, hoping to make gains there that he could then trade at the negotiating table for the all-critical holy city of Jerusalem. But four years of fighting in Egypt never produced anything more than a stalemate near the coast. At last, he went away again, having accomplished exactly nothing at a high cost in death and suffering.

Yet Jerusalem would fall back into Christian hands again for one last, brief span of time. This feat would be accomplished not through warfare but through diplomacy, by one of the more unusual European monarchs of the Middle Ages — and another of those who had a less than congenial relationship with papal power.

Holy Roman Emperor Frederick II was a man of diverse parts and considerable brilliance. People called him “the wonder of the age” in recognition of his interests in the natural world, philosophy, theology, languages, and mathematics. He had grown up on the island of Sicily, close to the Muslim sphere of influence. This, combined with his insatiable intellectual curiosity, gave him fluency in Arabic and a relatively nonprejudicial view of Islam, even as he remained a staunch Christian himself. He was, in short, a cosmopolitan man of the world, a quality not usually associated with Crusaders.

This same quality did nothing to endear him to a Catholic Church which Innocent III had left more dogmatic and intolerant than ever. Innocent’s successor Honorius III shared his predecessor’s attitude toward the papacy and its powers, although he lacked Innocent’s creativity and energy. After Frederick was crowned Holy Roman Emperor in 1220, Honorius kept pressing him to lead a Crusade to reclaim Jerusalem, and Frederick kept delaying. Finally, Honorius gave him a deadline: leave for the Holy Land by 1227 or be excommunicated. Frederick did indeed sail that year, only to turn around and come home again, claiming to have fallen ill. Honorius had died just weeks before the emperor’s return, but his successor Pope Gregory IX followed through on his threat and excommunicated Frederick, with the tacit escape clause that he could be restored to God’s grace if he just made good on his earlier promise and led a proper Crusade to the Holy Land.

Frederick grudgingly did so, but he took a dramatically different tack from any Crusader before him upon reaching Palestine. Instead of hurling himself immediately into the fray against the Muslims, he asked to meet personally with Sultan Al-Kamil — the same leader who had recently spent four years battling the Fifth Crusade to a standstill in Egypt — to see if they couldn’t work out their differences like mutually honorable men. Impressed by his counterpart’s easy Arabic and forthright manner when they broke bread together, Al-Kamil agreed to give back to the Christians Acre and Jerusalem if they would but allow the Muslims to keep the Dome of the Rock, their religion’s most sacred shrine in Jerusalem, which stood on the purported site of Solomon’s temple. Al-Kamil promised, however, that Christian pilgrims would be free to visit even here, as long as they behaved themselves and respected their hosts. Frederick wasted no time in agreeing to his terms. It was an astonishing feat of diplomacy, accomplishing with a few hours of polite discussion what the Third, Fourth, and Fifth Crusades had not been able to by expending hundreds of thousands of lives and fortunes in gold. Christians everywhere ought to have rejoiced that Jerusalem — the whole original point of the Crusades — was theirs again, and that no one had had to die for this to happen.

But Pope Gregory IX wasn’t satisfied. He was if anything even more of a hardliner than Innocent and Honorius before him, spending much of his time authoring decrees to make it ever easier for the Inquisition to execute heretics. He now roundly condemned Frederick for leaving any part of Jerusalem in heathen hands, and refused to reverse his excommunication. Instead Gregory began fomenting a rebellion against him in the heart of his empire. But the erudite Frederick was not a man to challenge lightly to a duel of arms or words: he called Gregory a “Pharisee seated on the chair of pestilence, anointed with the oil of wickedness.” Poor Gregory’s stock “blasphemer” and “antichrist” descriptors paled by comparison. The spectacle that followed was bizarre even by the standards of the Middle Ages: Frederick sailed to Italy with the army he had not needed to employ against the Muslims, defeated the forces of the Papal States in battle, and more or less forced Gregory to reverse his excommunication at the point of a sword.

There followed another of the less inspiring periods in the history of the papacy and the Church. Between 1241, the year of Gregory’s death, and 1295 there were no fewer than fourteen separate popes, most of them doddering, reactionary old men. Christians seemed to become their own worst enemies everywhere. The local worthies in Jerusalem, for example, decided to renege on the deal Frederick had negotiated for them, overrunning the Dome of the Rock and kicking the Muslims out. This act hardened Muslim hearts against Christians once again, ensuring that no more such generous deals would be forthcoming. In 1244, Turkish Muslims took Jerusalem, massacring thousands of Christians in the aftermath. Thus ended the city’s tenure in Christian hands — permanently this time.

The Muslim world, which was at a pinnacle of wealth and intellectual and artistic accomplishment at this time, looked on Europe with contempt. And indeed, it is in some senses hard to blame them. Europe really was by comparison a benighted, paranoid, insular place, alternating spasms of otherworldly rapture with fruitless violence. An apocalyptic terror that marked the middle years of the thirteenth century was part and parcel of this mode of thinking and being.

In light of the millennial jitters that greeted the passing of the year 2000, many people today are surprised to learn that the equally ominous round number of the year 1000 came and went with very little expectation of the apocalypse foretold in the Book of Revelation. The fact is that, after it became clear to the earliest Christians that Jesus Christ wouldn’t be returning within some of his followers’ own lifetimes, and after Rome, Revelation’s “Whore of Babylon,” was co-opted by Christianity rather than annihilated by it, apocalyptic prophecies played relatively little role in Christian theology. Revelation, a book whose vicious, hate-drenched tone jars when read in conjunction with its pacifistic stablemates, was always the odd man out in the New Testament, such that many theologians preferred to more or less ignore it. Saint Augustine didn’t quite go that far, but he did insist that it should be read as metaphor, not as literal prophecy. And, as we have seen, where Augustine went the rest of the Church tended to follow. But that changed as the seemingly harmless-looking year of 1260 approached, thanks to a monk from the previous century named Joachim, from the southern Italian town of Fiore.

The now long-dead Joachim had been convinced that he had cracked the code of the temporal world’s chronology. He started with the Christian doctrine of the Holy Trinity: one God who contains within his infinite depths the Father, the Son, and the Holy Ghost. These corresponded, Joachim believed, to three predestined ages of the world. The Age of the Father had been that of the Old Testament God of the Jews, that stern, remote figure of laws and rites and commandments. The Age of the Son was the one in which the world currently found itself, that time of a New Covenant with a more loving, forgiving God who was open to all the peoples of the world. And still to come was the Age of the Spirit, when the world would be brutally cleansed of evildoers and unbelievers as predicted in the Book of Revelation, in order to make room for the righteous to live in peaceful harmony for the time that remained before the end of time as mortals know it.

The obvious question, then, was when the second age would give way to the third. And Joachim thought he knew the answer. The Gospel of Matthew opens by detailing Jesus’s mortal patrilineage, 42 male ancestors in all, beginning with the Old Testament patriarch Abraham and ending with Joseph, the husband of Mother Mary. (This interest in genealogy is odd on the face of it, given that Jesus was supposed to be the product of a virgin birth and thus presumably shared no blood with Abraham, Joseph, or any other male mortal. We’ll have occasion to return to that subject much later in this book, because this same patrilineage of Jesus is one of the motifs depicted in the Sistine Chapel. For now, though, we’ll table our cognitive dissonance.) Assuming that each generation spanned 30 years, this patrilineage meant that the Age of the Father had lasted 1260 years in all. And further assuming for consistency’s sake that the Age of the Son would be of the same duration, the apocalypse described in Revelation ought to come in the year 1260.

In 1254, Joachim’s calculations, which had previously been obscure, were popularized by a monk named Gherardo da Borgo in a book called The Everlasting Gospel. In its pages, Borgo embellished Joachim’s prophecies with more of his own, drawn from the endlessly flexible surrealistic imagery found in the Book of Revelation. According to his interpretation, Revelation predicted that a corrupt pope would be seated in Rome when Jesus made his return.

At the time that Borgo wrote his book, the current pope was Innocent IV, who was indeed one of the more venal of the age, notable for, in the understated words of Richard P. McBrien, “raising nepotism to a high art” and “erasing the distinction between Church revenues and personal revenues.” In no doubt as to what Borgo was getting at, Innocent promptly tossed him into prison for life, but his book continued to be passed from hand to hand among the literate believers of Europe, who read it to the many more who were not. By 1259, tens of thousands of penitents were clogging the streets of many a city and village, dressed only in dirty loincloths, weeping and begging for God’s mercy whilst lashing one another’s backs bloody with leather straps. The members of the apocalyptic cult became known as the Flagellents in recognition of their fondness for the scourging of the flesh. The Church, lacking sufficient Inquisitors to stamp out such a widespread movement, looked on in alarm at what had begun to take on the trappings of a whole new, divergent branch of Christianity, one that had little use for the traditional ceremonies and hierarchies. The Church’s saving grace was the fact that this unwelcome offshoot had a make-or-break date expiration attached. The year 1260 came and went without any sign of Jesus’s return, and the Flagellants mostly settled down to become obedient, orderly worshipers once again.

Excesses like these make it all too tempting to see late Medieval Christianity in general as Europe’s falsest of friends, keeping the continent mired in ignorance, superstition, and magical thinking when it could have been improving its lot. And there is something to this point of view — but it is far from a complete picture.

As I mentioned at the outset of this journey through the past, the Middle Ages are a muddle of imagery in the modern popular imagination, all of them springing from incomplete truths. One of the movies that play out in our minds is Monty Python and the Holy Grail: peasants tossing bound women into lakes, out of the belief that they will be proven to be witches if they should float, proven innocent if they should drown. This really was done in some times and places. But another image comes from The Name of the Rose: monks laboring tirelessly over illuminated manuscripts in dusty scriptoriums, preserving the treasures of the ancients against the onslaughts of indifferent Time. Both capture a facet of the full Medieval Christian experience.

For much of the Middle Ages, the Church was the only sanctuary of scholarship in Europe. Although the Bible and the works of the great early Christian theologians were considered the most important texts of all, they were by no means the sum total of what was copied and recopied and filed away, first in monastic libraries and then in universities of higher learning, close partners of the Church, the first of which was founded in Bologna in 1088.

From our modern perspective, there were just a couple of problems with this Medieval life of the mind. One was that it remained for centuries focused more on the preservation than the production of knowledge; whatever else it may have been, the Church was an intensely conservative institution, which tended to believe that everything truly worth writing had already been written. And the other was that the corpus of extant texts that were preserved was really rather small. Much was lost between the collapse of the Roman Empire of Antiquity and the time that Charlemagne first encouraged scribes to take up their quills again.

The first problem would not fade away for quite some time yet. But the second began to be remedied already during the twelfth century, thanks to a man named Gerard who was presumably a monk or clergyman of some sort, although we have no definitive documentation of his status. The sad fact is that, while we do know that he was born in the northern Italian town of Cremona around 1115, we know very little else about him beyond that. It appears that he became fascinated at an early age with the second-century astronomer and astrologer Ptolemy of Alexandria, of whose writings only a few scattered fragments still existed in Latin. Luckily for Gerard, the Muslim world had also taken a shine to the ancient thinker, preserving his works in exactly the concerted way that the Christians of earlier centuries had failed to do; the Muslims had translated Ptolemy’s books from the original Greek into Arabic, in which form they had been widely read for hundreds of years. And doubly luckily for Gerard, the Christians on the Iberian Peninsula were in the process of slowly pushing back the Muslim caliphates that had once dominated there. The city of Toledo, long the intellectual capital of Iberia, had recently fallen to Christian armies, opening up a treasure trove of translated ancient writings, from Ptolemy and many, many others.

The intrepid Gerard went to Toledo personally. His first challenge there was to learn Arabic. Once he had accomplished that not-inconsiderable feat, he spent the rest of his life translating into Latin no fewer than 71 separate works, not only from Ptolemy but from such other pivotal ancient thinkers as Archimedes, Euclid, Aristotle, Apollonius, and Galen. His translations would continue to shape the intellectual life of Europe until well beyond the end of the Middle Ages. Galen, for example, would still be the standard medical text as late as the eighteenth century. Small wonder that Sir Francis Bacon would write bluntly in the seventeenth century that “philosophy has come down to us through the Arabs.”

Literature and history followed on the heels of Gerard’s translations of philosophical texts. By the early thirteenth century, Europeans were reading Virgil, Ovid, Lucan, Terence, Cicero, Cato, and Seneca once again, all of these authors having been translated into Arabic by Muslims and then translated back into their original Latin by later Christians. Once Toledo’s libraries were exhausted, texts came to Europe from Jerusalem and the other places occupied by the Crusaders, including not least Constantinople; once the Fourth Crusaders had gotten done burning a large portion of that city’s libraries, there were still left behind many heretofore unknown Greek works, awaiting only translation into Latin with the aid of those Byzantine scholars who were also left behind. Some historians go so far as to claim on the basis of all this that the Renaissance in actuality began earlier than is typically stated, speaking of a “Twelfth Century Renaissance” that preceded the more famous one of 200 years later.

The best argument against such a claim is that most of the intellectual labor of the twelfth and thirteenth centuries was still dedicated to the preservation of old knowledge rather than the production of new. Although invention ran apace in Europe during the later Middle Ages in such practical fields as war-making and agriculture — siege engines, catapults, and crossbows were among the technological wonders of the time, as were windmills — men of arts, numbers, and letters were still looking almost exclusively to the past rather than to the present or future. Even so, the old knowledge that was recovered or appropriated from elsewhere was as revolutionary to the existing life of Europe as the innovations from whole cloth of many another age. For instance, the Hindu-Arabic number system, the best that has ever been invented, finally reached the West after people there had spent millennia futzing about with clunkier alternatives; imagine trying to do algebra using Roman numerals, which have that name for a reason. Another stroke of genius out of the East was the number zero, which only seemed obvious after the fact. These are just a couple of the countless mathematical innovations that reached late Medieval Europe from the world beyond its borders; tellingly, “algebra” itself is an Arabic word rather than a Greek or Latin one. And European mathematics was only one of the fields that benefited from the foreign infusion.

In light of all this, perhaps it is only fitting that the most important single Christian thinker of the age devoted so much of his energy to harmonizing all of this newly rediscovered or appropriated knowledge, most of it produced by non-Christians, with the faith that remained the overriding preoccupation of the European Middle Ages. His name was Saint Thomas Aquinas.

Thomas was born in 1225 in the Italian town of Roccasecca, which lies midway between Rome and Naples. He had a noble bloodline, with connections on his father’s side to the current line of Holy Roman Emperors and on his mother’s to Norman princes, but he cared almost from birth only for religion and learning. There is a story that, when he went off at age fourteen to study at the University of Naples, some of his fellow students proved that the fraternity-bro impulse is timeless by sending a comely young woman of the night to him in the room where he sat poring over his books. Far from giving in to temptation, Thomas chased her out of the room with a flaming brand as if she was the spawn of Satan himself. Afterward he burned a cross into the door she had befouled with her presence.

But he wasn’t all fire and brimstone. One friend described him as “soft-spoken, easy in conversation, cheerful and bland of countenance, generous in conduct, most patient, most prudent; radiant with charity and gentle piety; wondrous compassionate to the poor.” Once when he was sitting at table with King Louis IX of France, he drifted away on the wings of one of his reveries, muttering to himself something about having stumbled upon the “decisive argument” in one of his theological conundrums. The king, recognizing that he had a future saint and current genius at his side, was not offended, but merely called for his servants to provide Thomas with the parchment and pen he needed to record his insight.

Ordained as a friar and a priest, Thomas lived and studied at various times in Paris, Cologne, Orvieto, and Rome, producing an astonishingly large body of writings for a life that spanned less than 50 years. His central project was to reconcile the perceived conflict between faith-based or revealed knowledge and reason-based or empirically derived knowledge. The one was knowledge of God, the other knowledge only of this fallen world. As such, Saint Augustine had taught Christians to look on appeals to reason alone with extreme skepticism, as they should all things of this world. Augustine lamented at one point in his Confessions that he had let himself be distracted by the peculiar locomotion of a lizard moving across the ground in front of him, when he ought to have been contemplating the majesty of God. By his logic, the works of an ancient philosopher like Aristotle, who devoted most of his efforts to studies of the natural world, were not just a waste of time but an existential threat to the soul’s prospects for an an eternal reward in Heaven.

Thomas’s response was elegant and truthy. All Christians agreed, he stated, that God had created this world, fallen though it may presently be. Therefore he must also have created the natural order of causes and effects which marked it. And then too, God had created humans, giving them both a knowledge of certain innate truths of morality and spirituality which transcended reason — what scientists of a later epoch would come to call instinctive knowledge — and the ability to learn other, admittedly more prosaic truths about the world around them through the power of reason which he had granted them — i.e., what those same later scientists would call acquired knowledge. Why would God have given humans this latter ability if he didn’t intend for them to use it?

Thomas thus concluded that all knowledge was ultimately a gift of God, and as such worthy and even sacred. The human instinct to understand the temporal world was not a dangerous distraction but another way to celebrate God; the study of the world was just one more way of coming closer to its creator. Ancients like Aristotle, whom Thomas read and wrote about at enormous length, had only been responding to this natural human urge to know God when they observed and thought about the world around them, even if they hadn’t quite understood where the impulse to know came from. To be sure, humanity could not come to know all things through reason. “The highest knowledge we can have of God in this life,” wrote Thomas, “is to know that he is above all that we can think concerning him.” But humanity could learn much through reason. To do so was good and just, precisely what God wished for people to do.

Inevitably, this new way of thinking made many people who were wedded to the philosophy of Saint Augustine very uncomfortable. And not without good reason: Will Durant goes so far as to claim that it was Thomas Aquinas who “brought the Age of Faith to an end.” If so, he did not do so during his lifetime; he would be read more — and more approvingly — by the people of later centuries than those of his own. Had he been a bit less fortunate, he might very well have fallen afoul of the Inquisition and been executed for his ideas, a fate met by a smattering of his contemporaries whose intellectual wanderings took them into territory deemed too foreboding by the guardians of Church orthodoxy. As it was, some of his arguments were pronounced heretical by Pope John XXI in 1277, three years after his death. Just days later, the good pope was sitting in his study when the ceiling suddenly fell in on him, killing him instantly. Perhaps God really was on Thomas’s side…

Despite the best efforts of the reactionaries, Thomas Aquinas’s theology gradually insinuated itself into the broader tapestry of Christian theology in general, with many knock-on effects. For instance, his veneration of the ancient thinkers sparked the notion of a Purgatory that served as a sort of halfway house between Heaven and Hell, for souls like that of Aristotle who hadn’t known Jesus Christ during life and thus couldn’t make a nonstop trip to Heaven after death, but who hadn’t sinned egregiously or explicitly rejected him either, and thus hardly seemed worthy of the eternal torment that awaited down below. Such souls could eventually ascend to Heaven by recognizing the truths of Christianity from Purgatory. Early in the fourteenth century, the Italian poet Dante would produce what many consider the greatest single work of literature of the entire European Middle Ages. In addition to its many other merits, his Divine Comedy oozes the cutting-edge theology of his time. It is divided into three parts, one set in Hell, one in Heaven… and, tellingly, one in Purgatory. Absent a Saint Thomas Aquinas, it would have looked very different.

But, again, it would take quite some time for Thomas’s ideas to attain such a level of acceptance. Western European theology at the end of the thirteenth century was still balanced precariously — and, for many scholars, somewhat dangerously — between the old thinking represented by Saint Augustine and the new represented by the yet-to-be-canonized Thomas Aquinas.

If Christian thought was a mixed bag of reactionary and progressive impulses, Christianity’s fortunes in the world beyond Europe were in decided abeyance at this juncture. By 1300, not just Jerusalem but all of the Christian possessions in and around the Holy Land had been lost once again to Islam.

The last of the numbered Crusades had been ineffectual if not downright pathetic. In 1248, King Louis IX of France — the same one who once had that memorable meal with Thomas Aquinas — led a Seventh Crusade to Egypt with essentially the same plan that King Andrew II of Hungary had had before him: to make so much trouble for the sultan there that he would agree to give Jerusalem back to the Europeans just to get them out of his hair. It went even worse for Louis than it had for Andrew; in 1250, he and 10,000 of his men were captured. It took a mountain of gold and Louis’s sworn oath on a Bible to leave Egypt and never to attack it again to regain him his freedom.

Failing to learn from this humiliation, Louis decided to try again twenty years later. Unwilling to break his word by returning to Egypt and equally leery of attacking the well-fortified Jerusalem directly, he went after the Muslim land of Tunisia this time. Alas, he caught food poisoning and died shortly after making landfall there, whereupon the rest of his army decided to take his fate as an omen and go home. Thus ended the Eighth and last Crusade with nary an arrow being notched. Europeans lacked time and energy for more such expeditions to foreign climes, being distracted with a multitude of internal squabbles, many of them still involving popes and monarchs. And then there was the threat of the Mongol Empire, which had sprung upon Europe out of the distant Far East like a whirling dervish, to obliterate virtually the entire armies of Hungary and Poland in 1241 and then melt away as quickly as it had come. Europe spent the rest of the thirteenth century waiting nervously for the Mongols to return, unwilling to commit itself too much anywhere beyond its borders for fear of them. Fortuitously for Western civilization as we know it today, the Mongols found the riches of China and India more tempting than a comparatively poor and backward Europe.

All of these distractions left the door open wide for the Muslims to take the offensive and end the strange era of European enclaves in the Holy Land once and for all. One by one the Crusader States fell to the Muslim armies, their pleas for help from the mother continent falling upon deaf ears, until there was none of them left. Europe was so fractured and preoccupied that it even allowed Constantinople to be reconquered by the Byzantine rump states that the Fourth Crusaders had neglected to finish off. This event ended the prospect of a healing of the first great schism within Christianity on terms dictated by the Roman Church; the Byzantines in Constantinople returned to their old ways of worship, leavened bread and all.

And so ended the era of the Crusades, leaving behind a territorial status quo in 1295 that was pretty much the same as it had been in 1095, just before the First Crusade. There would be scattered attempts here and there to revive the Crusading spirit — Alexandria would be taken over and plundered for a bare few days by a rogue Christian army as late as 1365 — but the time of concentrated Christian holy war against Islam was over in the broad strokes.

All that was left were the echoes of the Crusades, which have reverberated down through the centuries to today. Dan Jones’s verdict on 200 years of Christian holy war is scathing but not insupportable.

Crusading outlived the Middle Ages, and remains today a favored trope of the alt-right, neo-Nazis, and Islamist terrorists, all of whom cleave to the decidedly shaky idea that it has defined Christian and Muslim relations for a millennium. They are not right, but they are not original in their error either. Crusading — a bastard hybrid of religion and violence, adopted as a vehicle for papal ambition but eventually allowed to run as it pleased, where it pleased, and against whom it pleased — was one of the Middle Ages’ most successful and enduringly poisonous ideas.

Inside Europe, the Crusader impulse had morphed into the Inquisition. A new, less rigid and dogmatic age of the intellect could just be glimpsed on the horizon, its character partially outlined in the writings of Thomas Aquinas, but it was no more than the merest smudge of a possibility as of yet. Before the light of the Renaissance could fully dawn, Europe would have to endure its worst century since the ones just before Charlemagne.

Did you enjoy this chapter? If so, please think about pitching in to help me make many more like it. You can pledge any amount you like.

(A full listing of print and online sources used will follow the final article in this series.)