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6. Frederick II |
How the wonder boy of the world became a fiery foe of the faith

Frederick II is drawn from Chapter Six, beginning on page 146, of Volume Seven, A Glorious Disaster of the twelve-volume historical series The Christians: Their First Two Thousand Years. If you would like to order this book please visit

Frederick II dazzled Europe in acquiring Jerusalem by negotiation, but his harem, his zoo, his arrogance, and a near 100-year-old pope triggered his downfall

Frederick II - How the wonder boy of the world became a fiery foe of the faith

Frederick II – How the wonder boy of the world became a fiery foe of the faith
In this undated illustration from the Bettman Archive, Emperor Frederick II parades on horseback through Vienna in January of 1237. He now stood at the pinnacle of his power, having seen his son Conrad made “king of the Romans” (which meant king of Germany). He would now set about the suppression of the Lombard League.

On September 27 of the year 1197 the emperor Henry VI, eldest surviving son of the great emperor Frederick Barbarossa and the most powerful ruler in Europe, did the one thing no one expected of him. He caught malaria and died. He was only thirty-two, and his early death set off a chain of events that would disrupt the whole continent for the next century and would place on center stage a figure often portrayed as the most extraordinary in medieval history. Whether this man was even minimally Christian historians have been debating ever since. That he was no friend of the thirteenth-century Christian church is beyond all argument.

The dead emperor was the third of eight children born of the long marital love affair between Frederick Barbarossa and Beatrix of Burgundy (their story is told in chapter 3). Their first two children, Henry’s older sister and brother, died young, so Henry became the heir. In probably the greatest coup of Barbarossa’s career, he saw this son of his, already emperor-designate over Germany and northern Italy, married to Constance of Sicily. Thus, when Constance inherited the Sicilian throne, Henry was able to unite nearly all Italy and much of western Europe under the imperial crown.

While Henry’s early death cut short his own role in that vast empire, it did not end the probability that his family, the mighty Hohenstaufens of Germany, would continue to rule his far-flung domain. Three years earlier Constance had given birth to a son whom she and Henry had named Frederick in honor of his grandfather.1 But now the child heir was fatherless and defenseless, vulnerable to the sort of cruel fate–blinding or poisoning, among the possibilities–so likely to befall a young ruler in such circumstances. Who could foresee that this boy would one day become the emperor Frederick II, known as Stupor Mundi–the “Wonder of the World”?

Aware of the peril to her son, Constance wasted no time in seeking a protector who would not deprive little Frederick of his heritage. This guardian must not be German, she decided; for too long she had watched her husband’s German comrades despoil her beloved land. So she turned for help instead to the papacy, first to Pope Celestine IV and then, when he died soon afterward, to Pope Innocent III, designating Frederick in her will as a ward of the pope.

Empress Constance’s immediate goals were to consolidate her son’s position as heir to the Sicilian throne and to neutralize the growing ambitions of Markwald of Anweiler, a former aide to her husband whose army was moving from a base in northeast Italy into the central Italian possessions of the Sicilian crown. She professed indifference to her son’s right to rule the German states and northern Italy, meaning the whole northern segment of her husband’s empire. It was Sicily that mattered to her.

Her distaste for Frederick’s German heritage was of profound significance to Innocent. What the papacy of the twelfth and thirteenth centuries feared most was encirclement by an imperial ruler who controlled both Sicily to the south (whose kingdom included much of southern Italy) and also imperial Germany to the north (whose empire included much of northern Italy). Wedged between them were the papal states, ostensibly but rarely more than loosely controlled by the pope. For more than a century reformist popes had struggled to shore up the sphere of papal independence. How could a pope fulfill his divinely ordained role as guardian of the moral law, effectively guiding kings and emperors, from a position of temporal helplessness? It was deemed crucial that, at the very least, the papal states preserve their autonomy. “The papacy could not function successfully as a homeless, wandering power at the mercy of some secular ruler,” writes Innocent’s biographer Jane Sayers. “It needed freedom from secular control and power enough to enforce its message.”

Given, therefore, the prospect that Markwald might well deprive Frederick of much, if not eventually all, of his inheritance, Innocent hastened to rally allies who might stop the ambitious German. Yet no sooner had the pope’s relationship with Constance begun to bear fruit than fate once again stacked the odds against little Frederick. Constance fell ill and died, depriving the boy of his most devoted guardian. It was November 1198, and he was not quite four.

By now ensconced at Palermo, Frederick was completely at the mercy of a council of men with no loyalty to him beyond a pledge to the pope, and he well may have discerned, child though he was, that events were moving with chaotic speed. Sicily would be fought over during the next several years by a welter of armed adventurers, with the Germans under Markwald eventually seizing the upper hand. The young monarch’s capture was only a matter of time and would become a signature event in his life, revealing both the brazen audacity and the haughty awareness of his own majesty that he would display so often as an adult. Describing his capture at age seven, an admirer wrote to the pope that Frederick “threw himself upon those who were about to seize him, trying with all his force to ward off the arm of him who dared to lay his hand upon the sacred body of the Lord’s anointed.”

The Lord’s anointed seemed, by all odds, doomed, however: Markwald could never permit the kingdom’s rightful heir to survive. But Markwald had problems of his own. Wracked with pain from a kidney stone, he consented to surgery, and it killed him. Frederick was transferred for a time to the custody of another German functionary, one less ruthless than Markwald, and eventually to a representative of the pope.

Though the years until he reached his majority at fourteen are among the least documented of his life, there is little doubt he was trained by the finest tutors, including a cleric who would become Innocent’s successor. But Frederick was far from a sedentary bookworm. He had the run of Palermo’s exotic streets, and he made the most of it, soaking up the cultures of Norman Sicilians, Germans, Greeks, Jews, and Arab Muslims. Here is where his apprenticeship in languages took place. He would master six, some sources say. Here, too, may have begun his drift toward religious skepticism or, in any event, his lifelong respect for the Islamic faith. He also spent time at summer palaces opening on vast royal parks that teemed with wildlife, where he roamed at will, nurturing a love for nature and for the hunt that would remain lifelong passions. Thus he grew up, heir apparent to his father’s immense empire but with a firm hold on none of it.

The pope was his sole ally, and even the pope’s support was of necessity conditional. He could scarcely watch papal authority wither under the bullying of an omnipotent temporal tyrant. As Frederick soon perceived, the pope must strongly support his claim to his mother’s heritage in the south while somehow thwarting him from asserting his claim to his father’s heritage in the north. This would require of Innocent a deft exercise of papal power. Still, power and academic competence came naturally to Innocent; he had grown up surrounded by them. Born Lothar dei Conti of Segni in a family of well-connected Italian aristocrats, Innocent had studied with some of the most cultivated minds of his day in the schools of Paris. At one point he even crossed the channel to visit the shrine of St. Thomas Becket, the martyr who had defied the English crown in defense of church prerogatives (see sidebar, pages 96—97). Becket was an international symbol of clerical courage, and Innocent had clearly admired him.

Even as a cardinal Innocent had begun to spell out his conception of the unique status of the pope as St. Peter’s successor. When he was elected to the highest ecclesiastical office in 1198, at about age thirty-seven, he left no doubt about his views. “Who am I myself or what was the house of my father that I am permitted to sit above kings, to possess the throne of glory?” he exclaimed in his consecration sermon. “For it is to me that the words of the prophet apply: ‘I have placed you above people and kingdoms that you may uproot and destroy as well as build and plant.’ . . . See therefore what kind of servant he is who commands the whole family. . . . He is the mediator between God and man, less than God but greater than man.”

Less than God but greater than man. For centuries historians have chewed over this and similarly sweeping pontifical declarations by Innocent, with some scholars describing his ambition for papal power as infinite. Yet this is most certainly false. Innocent did not doubt that temporal power was inferior to religious power, as the moon relied on the sun for light, or that he had the right to rebuke and punish kings for moral transgressions or for interference in the church’s sphere of influence. But he was also a shrewd and practical person with little desire, for the most part, to meddle in strictly temporal affairs. Moreover, he still believed in the old doctrine of the “two swords,” meaning that although the spiritual power was superior to the temporal, the spiritual authority must not seek temporal control over temporal kingdoms. Such was the man to whom Frederick would be required, again and again, to turn for assistance.

Needless to say, the German aristocracy had not been waiting quietly for Frederick to come of age. No sooner had Henry VI died than a destructive civil war erupted in Germany, with Henry’s brother Philip of Hohenstaufen at first fighting on behalf of his young nephew’s claim to the German imperial throne against the forces of Otto of Brunswick, nominee of the rival Welf family for emperor. But Philip’s supporters were not about to risk their lives for a boy in Sicily they had never seen, and they elected Philip emperor instead. This presented Innocent III with three options. He could uphold the claim of Frederick, a boy with apparently no prospect of asserting authority in the empire’s northern lands (fortunately, of course, from the papal point of view). Alternatively, he could throw in his lot with Philip, who seemed to command the support of a majority of German princes, though his relations with the papacy were abysmal. Or, third, he could attempt to boost Otto of Brunswick, who was on much better terms with the church. In 1201 Innocent made his decision. He proclaimed Otto emperor-elect.

Otto certainly seemed like a reasonable choice. Even with the pope on his side, however, he took years to consolidate his support in Germany and would have failed altogether had not his rival Philip been murdered in 1209 by a Bavarian count. And how could a self-respecting Welf emperor like Otto rest comfortably in Germany with a Hohenstaufen upstart like young Frederick on the loose in Palermo? Otto therefore turned his back on Germany and struck south at Frederick, violating an oath Innocent had required him to make. The pope’s prompt response was to excommunicate his man and later to depose him.

Within two years Otto, now a renegade in papal eyes, had conquered most of central Italy and was poised to invade Frederick’s territory in the south. Yet like many powerful men after a series of triumphs, he underestimated his rival, whom he considered a somewhat unprepossessing youth. Frederick by now was eighteen and had a wife and a new son (named Henry), but there was no good reason for anybody to believe he could outmaneuver old Otto. This is precisely what he now did, though, through a series of brilliant gambles blessed with hairbreadth escapes.

In fact, Frederick realized, there were some things already in his favor. Otto’s behavior had alienated a number of German magnates, who now invited Frederick north to seize his patrimony, meaning the German royal crown.2 How could he manage to do this with such limited forces as he commanded bottled up in Sicily? Against the emphatic pleadings of his wife and nobles, he slipped out of Palermo bound for Rome, his first goal being to secure the blessings and bullion of the pope.

Innocent’s options, as Frederick well knew, were narrowed down to two. Would he support Otto, the man who had already betrayed him once? Or would he support Frederick, the man he had sustained through a perilous childhood and had consistently supported as king of Sicily–even if this did mean uniting north and south under a single ruler? The choice was obvious. Arriving in Rome, Frederick happily declared the papacy his “protector and benefactor,” gave every evidence of a lifetime allegiance to it, easily won the pope’s blessing and bullion, and headed for Germany. Meanwhile, Otto left his army in Italy and also hastened northward to head him off.

It was now that Frederick would first establish his reputation for theatrics and spectacle. Lombard cities such as Milan, allied to Otto and lying like wolves along his path, would be richly rewarded if they caught him. Even if Frederick somehow got past them, Otto could remain confident that the narrow Alpine passes beyond could easily be rendered impenetrable. But some towns were friendly, and Frederick, driven by that wellspring of energy that would fuel his whole life, slipped from one to another like a fox. On the banks of the Lambro River after a lengthy night’s trek, however, all seemed lost. He and his small escort rode straight into a Milanese trap. His guards were slaughtered. Frederick, it seemed, was finally caught. But suddenly he leaped, like a lithe gazelle, onto a riderless horse, rode bareback into the Lambro, and escaped on the other side.

He then zigzagged through the Alps, taking trails barely marked, bypassing Otto’s vigilant posts on the main road, and ultimately showing up with a recruited escort of three hundred before the gates of neutral Constance, where the Rhine broadens into a lake of the same name. Inside the city walls the chefs of Otto’s advance party had prepared a big dinner for the emperor, expected shortly. Here Innocent’s help again proved decisive. When the local bishop refused to open the gates, a papal nuncio accompanying Frederick read out the pope’s sentence of excommunication against Otto. The wavering bishop was won over, the gates were flung open, and Frederick’s party moved in and (presumably) ate the dinner. Otto’s fury when he arrived an hour or so later can be imagined.

From that moment Frederick’s fortunes soared. With a major assist from Philip Augustus of France, whose military victory over Otto at Bouvines in 1214 cost the excommunicate emperor any remaining credibility, Frederick marched through Germany from one triumph to another on his way to the historic seat of German kings, the city of Aachen. There, on July 15, 1215, he took his place on the throne of Charlemagne and was crowned “king of the Romans” by the archbishop of Mainz. In the same year, Otto was deposed as emperor.3

At his coronation Frederick did something that has baffled historians to this day. Taking the cross, he vowed to lead a crusade. Was this the spontaneous gesture of a still-impulsive youth, as some have maintained? Not likely. The coordinated preaching throughout the following day suggests a planned event. Or was Frederick bent on ingratiating himself with Innocent III? There was no need for that. He had already conceded just about everything the pope wanted.

So what did propel this indifferent son of the church, a man fluent in Arabic and no ideological enemy of Islam, known for lavishing money on just about anything but churches, to take up the crusader cross? Surely it was his sense of high destiny. What better way to signal his elevation as the unrivaled leader of Christendom, heir to Charlemagne and Frederick Barbarossa, than an expedition to the Holy Land? But the oath he took soon became a thorny burden. As pope after pope demanded he fulfill it, he balked.

A year and a day after the crowning of Frederick at Aachen, on July 16, 1216, Pope Innocent III died of a fever at Perugia, Italy. He departed this life with what he doubtless saw as his greatest endeavor magnificently completed. The Fourth Lateran Council of 1215 had attracted the largest gathering of bishops of any assemblage in the Middle Ages and had addressed a host of issues dear to Innocent’s heart, among them the vanishing Christian presence in the Holy Land, the rapid growth of heretical teaching, and the corruption and indolence of many clergy.

Historians would later castigate Innocent III for his role in two major Christian calamities, the Fourth Crusade (see chapter 5) and the brutal suppression of the Cathar heresy (see sidebar, pages 230—233). His later defenders, while conceding his imprudence in trusting untrustworthy people, vehemently deny that he had any role in the Fourth Crusade’s attack on Christian Constantinople and insist that the penalties imposed by the Inquisition on the Cathars and the inquisitional system that tried them were fair and reasonable. It is also noteworthy, they say, that Innocent approved the founding of the Dominican and the Franciscan orders, both widely deplored at the time but resolutely supported by Innocent.4

Perhaps, as things would turn out, Innocent’s worst miscall was his failure to perceive the true nature of the man he had raised to European ascendancy, the redoubtable Frederick. Innocent’s successor, Censio Savelli, who became Pope Honorius III, was the first to discover what Frederick’s success portended. He may have suspected it already, having been Frederick’s papally appointed tutor. Right from the start the new pope began calling the emperor’s attention to his promised crusade, typically causing Frederick to renew the promise and then continue to ignore it. Other things interested him more.

Germany was not one of them, however, although he felt obliged to remain there for a few years. He discovered that generations of civil war had allowed the aristocracy to wrest too much power from the crown for his taste. He would put in place his own ideas of governance in his beloved kingdom of Sicily, to which he decamped in 1220, leaving behind his son Henry to run Germany.

He established his seat of government at Capua, twenty-five miles north of Naples. Like most medieval monarchs, however, he spent much of his time on the road, moving from fortress to fortress with his court and the elaborate menagerie of birds and animals that became his trademark eccentricity. Foremost in his mind were two goals: the suppression of all resistance to his authority and the creation of a centralized imperial state such as Europe had not seen in centuries.

To Frederick it was intolerable that tens of thousands of Muslims on the island of Sicily enjoyed de facto independence. His answer: a pitiless policy of ethnic cleansing as he battered down their strongholds. His sympathy with Islam, that is, did not extend to allowing Muslims or anyone else “independence.” But soon another thought occurred to him. Why not put their talents to use on his own behalf? In 1223 he began a mass deportation of Muslims, some fifteen thousand or more, to the town of Lucera on the Apulian plain in southern Italy. Isolated there and completely dependent on the emperor’s favor, these Islamic serfs were to provide some of his most trusted light troops and bodyguards during the rest of his reign.5

The emperor was just as harsh in his other administrative measures. For example, he seized almost every castle of strategic importance. He established extensive imperial trading monopolies. He even founded a university at Naples to provide him with a lay-educated bureaucracy untainted with Christian assumptions and used them to replace local officials.

But what about his pledge to lead a crusade? The pope, naturally, wanted to know. Not yet, Frederick replied again and again. And finally, give him two more years, he said at last; all would be ready in 1225. This time Honorius was sure Frederick possessed the needed spur. The emperor’s first wife had died in 1222, and he had subsequently betrothed himself to the young Yolande of Brienne, hereditary queen of Jerusalem. What better incentive for a crusade than to claim another kingdom as his own?

As the promised year approached, however, it became apparent that Frederick was no closer to departure, and another two-year deadline was fixed. This time, though, the agreement between pope and emperor included a cudgel: if Frederick dallied, he was to be excommunicated. But when 1227 arrived, it was not procrastination that thwarted the promised Crusade; it was disease. As throngs of knights and retainers gathered midsummer in the scorched camps outside the port of Brindisi, a deadly epidemic broke out. Hundreds died, one of them the husband of the saintly Elizabeth, landgravine of Thuringia (see sidebar, page 123); many others, including the emperor, hastily boarded ships and left. But by this time he, too, was sick. He returned to his kingdom–just in time to receive word that Honorius was dead.

Frederick had regarded the old pope as a man in his dotage and may now have expected his successor to be considerably younger. But Ugolino of Conti was not younger. He was five years older than Honorius when, at the age of eighty-four, he became Pope Gregory IX. He was (and is) regarded by fervent admirers of Frederick as a “hateful” old man who began his pontificate by excommunicating the emperor as an oath breaker and malingerer, and continued to harangue, deplore, and thwart him for the ensuing fourteen years.

Gregory IX simply would not believe that Frederick’s illness was real, and, unlike Honorius, he was not a man to bite his tongue. He also possessed the iron will of Innocent III; indeed, he was Innocent’s nephew and was fiercely loyal to his uncle’s basic policies. So Gregory soon established himself as an octogenarian activist. He canonized Francis of Assisi in 1228, having first saved the Franciscan order from almost certain disintegration after Francis’s death (see chapter 10). He ramped up the papal campaign against heresy. He ordered a compilation of canon law that would remain in use for centuries. To quail before anyone playing games with a crusader oath was not in his character.

What galled him most, however, were Frederick’s larger pretensions. As Frederick strengthened his hold over the southern half of his empire, gathering every rein in his imperial fist, Gregory saw that Rome, too, would soon wind up in the imperial harness. He resolved that when the inevitable contract was drawn between Frederick and the papacy, his own indelible stamp must appear on the terms.

Frederick seems to have been baffled at first by the pope’s decision to excommunicate him. He was in uncharted waters here, but that is where he excelled. It occurred to him that no excommunicate had ever led a crusade. In theory, at least, no excommunicate could, for if he tried, no knight or soldier could obey his commands. Be that as it might, Frederick resolved, he would call Gregory’s bluff and see what the pope wanted more: a liberated Jerusalem or a humiliated Holy Roman Emperor.

The army that shipped to the Holy Land in 1228 and is recorded historically as the Sixth Crusade consisted of Muslim bowmen, fifteen hundred knights, and about ten thousand infantry–a relatively paltry force for such an undertaking. They joined a nearly equal number of crusaders waiting at Acre, but even the two forces together were no juggernaut. Frederick had an ace up his sleeve, however. For a leader of Christendom, he boasted a remarkably close relationship with a powerful Muslim ruler, al-Kamil, the sultan of Egypt, the same sultan who had befriended Francis of Assisi ten years before (see chapter 10). They had exchanged embassies, lavished gifts upon each other, and discussed the possibility of a deal before Frederick had even left Italy. What al-Kamil had to offer was Jerusalem itself. What Frederick could supply in return was aid in al-Kamil’s struggle with the sultan of Damascus.

By the time Frederick disembarked in the Holy Land, however, the political landscape had shifted. The sultan of Damascus had died, and al-Kamil no longer wished to treat with Frederick. No matter. Frederick would not be put off. His representatives cajoled, flattered, reasoned, and threatened. At one point he menacingly marched his army south with orders issued not in his own name but in the name of God and Christendom so that the Templars and Hospitallers would obey them without qualm. And to the enduring shock of Europe, al-Kamil came around. He agreed to turn over the three original Christian holy cities–Nazareth, Bethlehem, and Jerusalem (minus the Temple Mount)–to the crusaders’ control, along with a corridor to the coast.

Critics of Frederick would never let him forget that the Treaty of Jaffa, which he signed with al-Kamil, left Jerusalem defenseless, that it included no enforceable guarantees, that it was based on the word of a Muslim ruler who might repudiate it on a whim. Even so, it was a colossal achievement, fully justifying Frederick’s state entry into Jerusalem in March 1229 with his knights and several Catholic bishops. There, in the Church of the Holy Sepulchre, he was crowned king of Jerusalem–or rather, more precisely, crowned himself.

Even at this moment of triumph, however, Frederick’s position remained precarious, writes his biographer David Abulafia (Frederick II: A Medieval Emperor). The eastern Christians would have nothing to do with him, and the loyalty of some in his own camp was in doubt. Furthermore, he was inadvertently alienating the Muslims by his indifference to his own faith. They were shocked, for instance, at his mockery of Christians. “What is the point of the grill over the doors of the mosque?” the emperor asked his hosts at one point. “To keep out the sparrows,” they replied, upon which Frederick reportedly quipped, “Yet Allah has brought swine among you after all.” On another occasion he assured the Muslims that they need not silence the muezzins on his account since “my chief aim in passing the night in Jerusalem was to hear the call to prayer given by the muezzins, and their cries of praise to God during the night.” His last moments in the Holy Land became a jarring reminder of the ugly crosscurrents he had weathered: as his company made their way to the harbor in Acre, they were pelted with pig guts and offal by a riotous group of butchers.

Frederick’s success put the pope in an awkward position. Gregory had spent the year of the emperor’s absence fomenting rebellion, recruiting and subsidizing armies to invade Frederick’s realm, sabotaging the crusade, and spreading rumors of its failure and even of Frederick’s death. With Frederick’s triumphant return and the rapid collapse of opposition, Gregory had little choice but to reach an understanding with him. It is a measure of the papacy’s moral authority and the stigma of excommunication that even at this stage Gregory could wrest concessions from Frederick on behalf of the Sicilian clergy. Relenting at last, he lifted the ban of excommunication in August 1230, after which he and Frederick dined together at Anagni, about thirty miles southeast of Rome, an amicable interlude amid years of bitterness.

Restored as a Christian communicant, with Jerusalem now in his territory and with Pope Gregory at least briefly acquiescent, Frederick could return to his court at Capua and enjoy the fruits of his labors. Not that he actually slowed down. Only one year later, after prodigious research into all the laws of the land as well as other legal systems, Frederick promulgated the Constitutions of Melfi, which stand as the preeminent legal code of the Middle Ages. Whether the Constitutions deserve comparison with the Code of Justinian is a matter of debate; probably not. But they unquestionably confirm much about Frederick the man and his conception of royal power.

Thus, they vigorously embraced the principle of imperial authority as sacred: “To discuss the Emperor’s judgments, decrees, and statutes is sacrilege.” So was any questioning of the worthiness of his officials. After all, the emperor was “the terrestrial incarnation of divine justice, the supreme representative of God’s will” in the sphere of political order. Nor would any questioning be permitted in the religious sphere. Heresy, too, amounted to treason, and if inquisitions were required to root it out, so be it. Frederick’s attitude toward heresy would become a matter of profound embarrassment to later admirers trying to present him as the embodiment of enlightened secular indifference toward theological squabbles. Some try to explain his crackdowns as sops to the pope, but, in fact, his stern suppression of heresy is simply consistent with his attitude toward dissent of any type.

Also much admired has been his habit of objective inquiry. He communicated with the best minds in the world, whatever their background, including Jews in Spain, Muslims in Egypt, and his own celebrity-laden court. What proof is there, he wanted to know, of the eternity of matter? What is the true nature of volcanoes and geysers–and of paradise too? His biographer Patience Andrewes (Frederick II of Hohenstaufen) depicts him as embracing the Cistercians for their advanced methods of farming, borrowing their expertise and experimenting with various crops, including indigo and henna. He picked the brain of Leonardo of Pisa, known as Fibonacci, perhaps the age’s leading mathematician. He abolished trial by ordeal for the sound reason that “these judgments of God by ordeal which men call ‘truth revealing’ might better be styled ‘truth concealing’.”

His intellectual curiosity knew no bounds, it was said, and, unhappily, this seems to have been literally true; it became apparent that Frederick’s vaunted intellectual virtues were offset by dark and sometimes monstrous flaws. Stories were widely told of his indulgence in grotesque experiments. He was said to have had children raised by nurses who never spoke to them, for instance, to see how they would communicate on their own. (They died.) He had a man sealed in a wine vat to test whether a soul could be spotted escaping upon his death. (It wasn’t.) To determine whether food digested better in a man at rest or a man at work, he had two such men cut open. (Conclusion unrecorded.) And although he incorporated relatively advanced provisions regarding women into his legal code, he treated his wives in the manner of a pasha, isolating them from the life of his court by means of menacing eunuch guards.

The emperor’s interest in other religions is justifiably extolled, as well as the lengths to which he went to disprove a blood libel against German Jews. But although he granted Jews economic privileges, he also attempted to expand his official authority over them, stipulating that they were “serfs of our chamber,” and he had no qualms about enforcing a rule that they wear special clothing. His attitude toward Muslims was similarly complex: from their persecutor in Sicily he evolved into their protector in Lucera, so long as their fate was utterly dependent upon his whim. He stocked his court with Muslim dancing girls–his “harem,” whispered the justly suspicious critics–and even slaves, who included black African page boys.

Without doubt, however, Frederick’s singular personal achievement in intellectual terms, completed in the late 1240s, was the treatise De Arte Venandi cum Avibus (The Art of Hunting with Birds), a book that is far from the genial description of royal leisure its title might suggest. Indeed, this ornithological study, the first of its kind, is the distillation of thirty years of careful observation of birds, especially falcons and their prey, from nesting habits to diseases.

Yet no matter how much time Frederick managed to spend roaming the forests of Europe with his falcons, more pressing matters always intervened. He had last seen Germany in 1220, after ensuring the election of his son Henry as king of the Romans (which meant king of Germany). By 1231, however, he was hearing rumblings from German princes regarding the behavior of his heir. Henry, now a young man who hardly knew his father, had developed decided views on how Germany should be governed. For the first time not everything was going Frederick’s way.

Unamused by his son’s gestures of independence, he summoned a diet at Ravenna, in northern Italy, for November 1231, which he expected Henry to attend. What he did not anticipate, although perhaps he should have, was that several Lombard cities, led by Milan, would choose this moment to challenge his authority in a manner he could not dismiss.

In the relationship between some Lombard cities and Frederick, it was hard to say which side more heartily detested the other. At the cost of decades of strife, some of these cities had developed as largely self-governing republics. Barbarossa, Frederick’s grandfather, had exhausted himself trying to force them to adhere to imperial rule; now they mounted resistance to his grandson.6 They could imagine no fate worse than to be brought to heel like the towns of southern Italy, with imperial bureaucrats replacing their local administration.

For his part, Frederick considered municipal self-governance an abomination. If that weren’t enough, he had never forgiven Milan for its lack of enthusiasm at his accession and for its refusal to honor him with the iron crown symbolic of kingship over Italy. Further stoking his resentment was a bitter historical memory: the defeat of Barbarossa at Legnano.

Milan and its allies seem to have considered the gathering at Ravenna a threat, another imperial move against their liberties. Whatever the reason, they blocked the major passes through the Alps and thus the path to Ravenna. Frederick rescheduled his meeting with Henry for Easter in ancient Aquileia, a Roman city in northeast Italy near the Adriatic, northwest of Trieste and not far from fateful Legnano. This, he knew, his son would have no excuse for missing. Henry dutifully, if reluctantly, attended upon his father’s court there in the spring of 1232 and was quickly put in his place. If he wished to retain his crown, he would have to agree to strict rules of behavior, pledge to govern entirely in accord with Frederick’s wishes, and even agree to write a letter to the pope welcoming his own excommunication in the event that he disobeyed the emperor.

Such humiliating terms, far from settling the emperor’s German affairs, stoked resentment in young Henry’s proud heart. Within two years his agents were in secret negotiations with the Milanese. Shortly thereafter he took his defiance public, siding with the Rhineland cities against their overlords and thus instigating a civil war. But he had disastrously misjudged the spell that Frederick might still cast in the coming showdown.

Cool as always, the emperor swung into action. After securing Henry’s excommunication from the pope, he proceeded north in 1235 with a modest military escort and his ever-present menagerie, banking on his personal prestige and old loyalties to recruit an army on the spot. Henry’s support swiftly melted away, however, and the son found himself prostrate before his father, hoping for a clemency that could never be granted. He would spend the rest of his short life in one dungeon or another, until he could endure it no longer. At the age of thirty, during a transfer to yet another prison, he killed himself by riding off a cliff.

Three matters now remained that required Frederick’s attention. Heading the list was his third marriage, to twenty-one-year-old Isabella of England in a ceremony at Worms attended by a stunning list of nobles and churchmen.7 Second, in early 1237 he arranged for his son Conrad to be elected king of the Romans, supplanting the ousted Henry and again securing the succession. And last but certainly not least, he was resolved to teach the Lombards a lesson.

The German princes did not have to be prodded into assisting Frederick, especially given the way he deployed the gold of his English wife’s dowry as payment. Nor was the pope in any position to openly help the Milanese, given their allegiance with the now-excommunicated Henry. In September 1237 Frederick left Germany for the final time, joining an army of perhaps fifteen thousand that he had amassed in northern Italy. By November they were engaged in a complicated duel with a Milanese army of ten thousand, which kept the emperor at bay by using the region’s marshes and rivers as shields.

Frederick knew he must break the deadlock or squander the year, so his army noisily feinted in the direction of winter quarters, thus persuading the Milanese to drop their guard. Moving leisurely back toward their city, they were ambushed at Cortenuova by Frederick’s troops, who rushed into the fray shouting, “Soldiers of the emperor” and “soldiers of Rome.” The imperial forces not only cut down the Milanese in droves; they captured Milan’s symbolic carroccio, a sacred wagon emblematic of the city. This he deftly exploited to drive a wedge between the pope and the people of Rome by dispatching the carroccio as a gift to Rome, where it was received with an ecstasy befitting an oncoming conqueror.

Frederick was now at the height of his power. The conquest of all Lombardy seemed within his grasp, but at this point his thirst for vengeance unhinged his judgment. When Milan sued for peace on favorable terms for the emperor, he rejected the offer out of hand–probably the greatest mistake of his career. Only unconditional surrender would satisfy him, but to the Milanese such a demand was too ominous to contemplate. The Milanese stood fast, and when Frederick attacked Brescia, a Milanese ally, he was blocked there too, and he lost the advantage of momentum.

At this point Pope Gregory saw his chance and pounced, though it seems incredible that he would dare to openly challenge the emperor’s still formidable position. But beneath the superficial amity between the papacy and the imperial court lay deepening mistrust. The pope had watched with growing alarm as Frederick brought much of northern Italy to heel and began to install across all Italy his centralized lay bureaucracy. Surely, he would soon cast covetous eyes on Rome, the logical capital for the new caesar.

Gregory might be in his nineties, he might be hated by much of Rome’s citizenry, and his policies might be resisted by a growing cabal of cardinals, but the doughty old man never flinched. He began patiently building a case (pretext, his critics would call it) for Frederick’s second excommunication. Meanwhile, he quietly worked to bring Genoa and Venice into alliance with Milan and the Holy See, and he succeeded. Thus, in 1239 he dramatically renewed his excommunication of Frederick, releasing all Christians from their oaths of loyalty to him and committing his body “to Satan.” He categorically condemned the emperor for his treatment of the crusading orders, for his iniquitous personal behavior, and for his reportedly heretical views, and most especially rebuked him for his abuse of the Sicilian church. Lombardy was not mentioned.

Frederick, too, took his case to the world. Not only did he respond in a rare public speech in Padua, full of wounded indignation; he even sent a letter to all the kings of Europe, warning that “the abomination of Babylon goeth forth from the elders of the people . . . into wormwood they turned the fruits of justice” (Amos 5:7). Yet in this war of rhetoric the pope still ruled supreme, dishing out a papal bull of stunning vehemence, drawing heavily from the language of the Apocalypse. “Out of the sea rises up the Beast,” it began, “full of the names of blasphemy who, raging with the claws of the bear and the mouth of the lion and the limbs and likeness of the leopard, opens its mouth to blaspheme the Holy Name and ceases not to hurl its spears against the tabernacle of God and against the saints who dwell in heaven.”

Unable to ignore this galling challenge, Frederick upped the ante by declaring the pope the Antichrist and moving his army, often headed by his Muslim troops, against the papal states, with Rome itself as the ultimate objective. This was the final act so long feared by Gregory and his two predecessors. If Frederick took Rome, the papacy would very soon become a mere department in his government. What to do? Though the city had formidable defenses, most of its citizens seemed to be on the emperor’s side. Who would rally them?

Pope Gregory IX would. As the imperial forces reached Rome’s outskirts on February 22, 1240, this pope–nearly one hundred years old–issued one of the most remarkable calls to action in the history of the Holy See. Following a dramatic procession through the city, he took his tiara and placed it with the reliquary skulls of Peter and Paul, brought out on display for the occasion. This was a holy war against a renegade emperor, he thundered, a crusade against an excommunicate–and the saints themselves would defend Rome if no man among them had courage for the deed! An unfathomable and utterly unforeseen delirium swept the crowd. They took up crosses as signs of the holy cause, and at that moment Frederick’s advantage completely vanished. He had no appetite for conquering Rome if it would require a devastating siege, for that would confirm every charge the papacy had ever leveled at him.

He would have just one more chance to best this pope, whom he now hated with every fiber of his being. A year later he assembled his forces for a second attempt to march triumphantly and unopposed into the city. But fate or fortune or the will of God once again intervened: Pope Gregory IX, inconveniently, died. Frederick could hardly seize the city prior to the election of another pope: such blatant opportunism would permanently blacken his reputation.

Nor was this process speedy. The city’s most powerful layman, the senator Matteo Orsini, was pushing for a quick election of someone who would mirror Gregory’s anti-imperial stance. To that end, he had locked the ten available cardinals in the decrepit Septizonium Palace, where their deadlocked debates degenerated into a two-month living nightmare. Oppressed by the heat and the stench of overflowing lavatories, harassed by Orsini’s threats and by guards who made their contribution to the discomfort by urinating onto the leaky roof above the episcopal heads, the cardinals became weak and ill. One of them, the Englishman Robert of Somercote, actually died. When they at last elected one of their number as Pope Celestine IV and were set free, the new pope, too, was so drained that he expired seventeen days later. By then the cardinals had fled to Anagni, whence they refused to return for another hellish conclave.

In the long months that followed, public sentiment throughout Europe gradually turned against Frederick. He was blamed at first for blockading Rome to hasten the election of a new pope and thus to make possible his own triumphal entry, then accused of tampering with the election by holding one of the cardinals prisoner. Not until June 25, 1243, nearly two years later, did the cardinals finally elect Sinibaldo of Fieschi as Pope Innocent IV. Frederick had great hopes for this highly intelligent, resourceful canon lawyer from Genoa, but of this optimism he was rapidly disabused. Innocent IV turned out to be Gregory IX all over again, except much younger and with sharper teeth.

Nevertheless, during the early months of Innocent’s pontificate he and Frederick appeared poised to settle a number of longstanding differences, agreeing at last to a face-to-face meeting at Narni, about sixty miles north of Rome. Whether the pope ever intended to appear on the appointed date is unknown; perhaps rumors that the emperor had resolved to take him prisoner changed his mind. Given the planning necessary for the plot that unfolded, however, it is likely that Innocent had been chafing under the terms of the proposed settlement and realized how difficult it would be to rebuff the emperor in person.

His failure to appear made him a fugitive from the imperial wrath. With his nephew and two cardinals in tow, he made a dash for the coast, where waiting galleys sped him to Genoa. From there he journeyed even farther, arriving in Lyon near Christmas of 1244. Though nominally part of the empire, it was beyond Frederick’s effective control. According to one contemporary chronicle, Frederick “ground his teeth like a satyr in his rage” when he heard of Innocent’s flight, but this was nothing compared to his anger at what transpired next, when Innocent called a general council of prelates for June 1245 to deal with the crises facing the church.

Although the emperor sent eloquent spokesmen on his behalf, the outcome was foreordained. On July 17 Innocent IV read out the judgment of the council, with particular emphasis on Frederick’s scandalous personal conduct.8 And this was a mere prelude. The pope stunned the world by announcing that the emperor was henceforth deposed, that his titles had been stripped from him, and that his subjects had no need to obey his commands. Frederick understood it as a declaration of war. “I have not yet lost my crowns, and I shall not lose them without shedding blood . . .” he raged. “For too long I have been the anvil; now I wish to be the hammer.”

Being the hammer involved, first of all, a propaganda onslaught in which he railed against the worldliness and wealth of the church. “Our priests,” he declared in one of his manifestos, “are slaves to the world, drunken with self-indulgence, who put God in the second place; the stream of their wealth has stifled their piety.” But the hammer was physical, too. Frederick’s cruel streak had always lurked just below the surface, and now it burst forth with indiscriminate abandon as he began to sense traitors in his midst. He accelerated a purge of the clergy, confiscating the property of anyone under suspicion; allied himself with regional strongmen whose brutality was notorious; stuffed his dungeons with hostages; bragged about the mass execution of prisoners; cut off the hands and feet of anyone with papers from the pope; and treated every anti-imperialist as a revolutionary who must be hanged–or perhaps blinded with a hot poker, stuffed into a sack with snakes, and thrown into the sea.

When he uncovered a plot (hatched by Innocent, he believed) to kill him and his illegitimate son Enzio, his fury was monumental. Anyone suspected of involvement was blinded, mutilated, and either burned to death or dragged throughout the countryside as a horrifying example of the fate to befall all would-be regicides. Eventually the emperor decided to strike directly at the source of his woes by rousting the pope from his sanctuary in Lyon. Yet even as his army wheeled in that direction, he received word from Enzio that Parma, a strategically vital city, had been seized in a coup led by a nephew of Innocent. He had no choice but to change plans; soon the walls of Parma were surrounded by his troops, preparing for a long siege.

Frederick made no secret of Parma’s likely fate. It would be razed, and in its place would rise a new city, Vittoria, whose construction he ordered begun even during the months in which his forces were reducing Parma’s citizens to a diet of scraps while terrorizing them with the daily spectacle of public executions outside the walls. But unfortunately for the emperor, his brutality made him irrational; his recklessness was matched by his folly. His entourage included not only the ubiquitous harem and menagerie and the imperial library but also a vast store of gold, jewels, and other treasures, a priceless crown among them. Furthermore, the fortifications of opulent Vittoria were unwontedly slipshod. On February 18, 1248, the emperor confidently rode off with his falcons and several boon companions for a fine winter hunt. Parma’s defenders thereupon feigned a sortie that duped the garrison and led it away from the town. With the imperial force out of sight, Parma’s desperate population raced out of the city, slaughtered Vittoria’s remaining forces, and carted off every last item of value.

Frederick reacted with his usual élan, riding through the night for nearly forty miles to Cremona to gather reinforcements, a feat of magnificent endurance for a man of fifty-three. He returned with troops to renew the assault on Parma, but there was no hiding the fact that he had suffered a staggering defeat, the worst of his career. The looted treasury, needed to pay his troops, could be refilled only through another levy on the already-resentful subjects of his southern realm. Even before Vittoria fell, his grip on Germany had weakened to the point that some northern princes had actually elected Count William of Holland as the new king of the Romans.

With pressure squeezing him from all sides, Frederick even began to imagine enemies where none existed. He had lost one of his two closest confidants at Parma when Thaddeus of Sessa was captured defending the treasury and then horribly executed. Now he himself turned on Pietro of La Vigna, who for twenty years had served him in a host of capacities, most memorably as ghostwriter of his polished proclamations. Three explanations have been offered. One, that Pietro conspired with the imperial physician to poison him, is almost certainly false–or if at all true, he may have been put up to it by the emperor’s enemies in Parma, where the doctor had been prisoner. More likely, Pietro was a victim of ugly rumors and of Frederick’s increasing paranoia. Another possibility, even more despicable, is that he was sacrificed so that the financially desperate monarch could get his hands on the wealth that Pietro had accumulated during his long service.

Blinded on Frederick’s orders and publicly abused, Pietro had no illusions about the further agony awaiting him before his inevitable execution. In April 1249, while being led to what he no doubt feared was some new horror, he reportedly asked his jailors if there was a clear path to the stone wall. Told that there was, he took it at full speed, smashing his skull with such violence that he died.

Now, too, Frederick’s body began to betray the toll of stress and physical hardship, succumbing with alarming frequency to a skin disease and other illnesses. But the worst blow of 1249 was the capture and imprisonment in Bologna of Frederick’s beloved son Enzio, an inspiring leader possessed of the same fearless energy as his father.9 Remarkably, however, the year 1250 began with the imperial forces holding their own against papal-backed troops and an outbreak of municipal insurrections. By September the situation had further improved, and Frederick, too, had revived during a summer in southern Italy. Confronting the pope in Lyon appeared a possibility again.

But by late fall, however, the emperor was beset by dysentery, eventually fell seriously ill with a fever, and in December summoned his chief officials to his side. To his dismay, he learned that in his stricken state he had been transported to Castle Fiorentino, a place he had never visited for the same reason that he had always avoided Florence. However irrationally, he feared an oracular prophecy foretelling the manner of his death: “You will die near the iron door in a place whose name will be formed by the word ‘flower’.”

Frederick never left Fiorentino alive. He designated his son Conrad as his heir, had himself clothed in the white habit of a Cistercian monk, and, just before dying, received last rites from Archbishop Berard of Palermo, whose loyalty spanned the emperor’s entire career. Buried in Palermo with appropriate magnificence in a tomb of red porphyry, he seemed to have ensured the survival of the Hohenstaufen dynasty. But it was not to be. The turmoil unleashed by his conflict with Innocent IV would spread with his death, and his entire male line–legitimate and bastard sons alike as well as two grandsons–would die off or be slain within a generation. Conrad died at twenty-six, only four years after his father. Conrad’s son, Conradin, was captured while still in his teens by the new Angevin masters of Sicily and publicly executed in Naples in an event that scandalized Europe.

In the short term, the papacy had won its deadly joust with the Hohenstaufen family. But Gregory IX and Innocent IV had walked some very dubious lines by deploying every weapon in the church’s arsenal–from excommunication to the preaching of crusades to the offer of indulgences to anyone who would take up arms–in what some Christians considered a purely political struggle. Others would argue that what the popes were striving for was a church beyond the control of national monarchies and governments that could prevent wars by acting as a neutral arbiter between nations. However, imperial propaganda further eroded papal prestige, as did populist preachers who followed it. But the papacy, although weakened, nevertheless survived, whereas the House of Hohenstaufen would shortly vanish from history. The Wonder of the World was its spectacular final bow.

This is the end of the Frederick II category article drawn from Chapter Six, beginning on page 146, of Volume Seven, A Glorious Disaster. To continue reading more about Frederick II from The Christians, Their First Two Thousand Years we suggest experiencing the rest of the book, complete with hundreds of magnificent illustrations, by ordering it at