Constitutions of Melfi and Court Patronage The papal invasion exposed some of the vulnerabilities of his southern kingdom, and Frederick was determined to enact a broad restructuring of the entire apparatus of government. The reconstitution of the Kingdom of Sicily that followed would prove a milestone in the history of European statehood. In 1231, the emperor issued the
Constitutions of Melfi as a comprehensive legal code which sought to centralize royal authority across the Kingdom of Sicily, replacing clerical officialdom with lay jurists trained in Roman law and establishing a tightly hierarchical administrative system reaching from the Emperor down to the most subordinate provincial functionary. The underlying philosophy was explicit: Frederick conceived of the Emperor as the living law upon earth, deriving authority directly from God, with the imperial office serving as the sole source of temporal justice. The code drew on Norman precedent and the emperor’s earlier assizes but refashioned both in a thoroughly ‘Romanized’ way, producing something qualitatively new in its breadth and scope. The code was not only collection of precedents but relatively intricate body of royal law which subject to change only by the sovereign’s will and the broad outlines of an entire structure of statehood. As such, the emperor considered the code to be the model framework for his larger territorial empire. Frederick’s idea of monarchy also manifested in the famous
augustalis, a gold coinage first issued in 1231, which captured something of this synthesis of Antiquity and contemporary tradition. A coin of fine quality, it bore the emperor’s own image in the manner of the ancient Caesars rather than a Christian symbol and announced in tangible form his conception of a secular imperial authority grounded in classical antiquity and Roman universalism. Besides his groundbreaking state-building, the emperor also garnered much prestige from the reputation of his cosmopolitan court. Based in Palermo and Foggia—as well as traveling with the ever-peripatetic emperor himself, Frederick’s court was one of the most vibrant intellectual hubs of the 13th century, and indeed in the entire medieval world. In many ways, it was the cultural nexus of its day. The emperor surrounded himself with famous scholars, jurists, poets, mathematicians, public intellectuals and natural philosophers drawn from across Europe and the Islamic world regardless of religion or origin, and interacted with them as an intellectual peer. Among the more notable attendants was the celebrated Scottish polymath
Michael Scotus, the astrologer
Guido Bonatti, the famous mathematician
Leonardo Fibonacci, the philosopher
Theodore of Antioch, the poet
Giacomo da Lentini and the jurist
Piero della Vigna, who became the emperor’s chief minister.
Dante would later identify Frederick’s court as the birthplace of Italian vernacular poetry, while contemporaries marveled at an environment that blended Roman legal rigor, Arabic philosophical inquiry, Byzantine administrative tradition, and the nascent literary culture of the Italian peninsula. In this way, the court of Frederick was, perhaps, the last great blossoming of the remarkable
Norman-Sicilian cultural synthesis.
Henry's Revolt While he may have temporarily made his peace with the pope, Frederick found the German princes another matter. Frederick's son
Henry VII (who was born 1211 in Sicily as the son of Frederick's first wife
Constance of Aragon) had caused their discontent with an aggressive policy against their privileges. This forced Henry to a complete capitulation, and the
Statutum in favorem principum ("Statute in favour of the princes"), issued at Worms, deprived the emperor of much of his sovereignty in Germany. Frederick summoned Henry to a meeting, which was held at
Aquileia in 1232. Henry confirmed his submission, but Frederick was nevertheless compelled to confirm the
Statutum at
Cividale soon afterwards. The situation for Frederick was also problematic in Lombardy after all the emperor's attempts to restore the Imperial authority in Lombardy with the help of Gregory IX (at the time, ousted from Rome by a revolt) turned to nothing in 1233. In the meantime, Henry in Germany had returned to an anti-princes policy, against his father's will: Frederick thus obtained his excommunication from Gregory IX (July 1234). Henry tried to muster an opposition in Germany and asked the Lombard cities to block the Alpine passes. In May 1235, Frederick went to Germany, taking with him no army, only a sumptuous entourage as a display of his power and wealth. News of his arrival spread quickly, and the rebellion disintegrated. As soon as July, he was able to force his son to renounce the crown and all his lands at Worms, where Henry was tried and imprisoned. Henry remained a prisoner in Apulia for the rest of his life until he reportedly committed suicide. Frederick II skillfully turned the complex challenge of Henry's rebellion into a chance to introduce "thorough and groundbreaking" reform of Germany and the way the empire was ruled. The Mainz Landfriede or
Constitutio Pacis, decreed at the Imperial Diet of 1235 in Mainz, became one of the
basic laws of the empire and provided that the princes should share the burden of local government in Germany. It was a testament to Frederick's considerable political strength, his increased prestige during the early 1230s, and sheer overpowering might that he succeeded in securing their support and rebinding them to Hohenstaufen power. In Germany, the Hohenstaufen and the Guelphs reconciled in 1235.
Otto the Child, the grandson of
Henry the Lion, had been deposed as Duke of
Bavaria and
Saxony in 1180, conveying the allodial Guelphic possessions to Frederick, who in return
enfeoffed Otto with the same lands and additional former Imperial possessions as the newly established Duke of
Brunswick-Lüneburg, ending the unclear status of the German Guelphs, who had been left without title and rank after 1180, and encouraging their cooperation.
The Struggle for Lombardy }} With peace north of the Alps, Frederick raised an army from the German princes to suppress the rebel cities in Lombardy. Gregory tried to stop the invasion with diplomatic moves but in vain. During his descent to Italy, Frederick had to divert his troops to quell a rebellion of
Frederick II, Duke of Austria. At
Vienna, in February 1237, he obtained the title of
King of the Romans for his 9-year-old son Conrad. After the failure of the negotiations between the Lombard cities, the pope and the Imperial diplomats, Frederick invaded Lombardy from
Verona. In November 1237, he won a great victory over the Lombard League at the
Battle of Cortenuova, displaying his capability as a strategist and battlefield leader able to manoeuvre and prevail in difficult situations. Frederick celebrated the victory with a triumph in
Cremona in the manner of an ancient
Roman emperor, with the captured
carroccio (later sent to the commune of Rome) and an elephant. The Imperial victory at Cortenuova sent shockwaves around Europe and burnished Frederick’s already legendary status. Now at the zenith of his power, Frederick's political preeminence was seemingly unassailable and his hegemony was recognized across almost all of Latin Christendom. Not since the days of his father and grandfather, or perhaps even since the heyday of the
Ottonians or
Salians, had Imperial sovereignty been in such a strong position. Frederick appeared to be master of Europe. With his supremacy now apparently secure, Frederick rejected any suit for conditional peace from his Lombard enemies, even from
Milan, his most implacable foe among the cities, which had sent a great sum of money. Perhaps from sober political calculation in light of years of Milanese opposition or simply hatred of the city, he was convinced that only complete military subjection could finally ensure Imperial dominance. The Emperor believed, perhaps, that any peace conducted with the Milanese—which must include the imposition of Imperial rule in the city by his official—would fail, because the Milanese would quickly overthrow his representatives after his departure from the region. Frederick's demand for total surrender spurred further resistance from Milan,
Brescia,
Bologna, and
Piacenza. In the spring of 1238, Frederick summoned a vast international army to aid in his campaign against the remaining insurgent cities, gathering troops from England, France, Hungary, the
Nicene Empire, and even a contingent sent by Muslim sultans in the east. From June, he
besieged Brescia. After savage fighting in which the emperor himself was nearly captured, Frederick was surprised at the city's continued defiance in the face of his large army and sent emissaries to negotiate its surrender. Frederick’s chief engineer was captured and forced to work against the besieging Imperial forces. The Brescians rejected the emperor's terms, and the siege continued into September, when torrential rains prevented any assault. After a last unsuccessful attack in October, Frederick was forced to raise the siege. Frederick's prestige suffered a blow, and the "legend of the emperor's invincibility" had been damaged. Regrouping as the year closed, it was not Frederick's political nous which failed him but a combination of bad luck and his incorrect assessment of the military resources required to subjugate the last few holdouts against Imperial authority in northern Italy.
Second Excommunication Gregory IX sensed vulnerability, and Frederick received the news of his excommunication by the pope in the first months of 1239 while his court was in
Padua. The emperor responded by expelling the
Franciscans and the
Dominicans from Lombardy, taking hostages from important northern Italian families, and electing his son
Enzo as Legate General and Imperial Vicar of Lombardy. Enzo soon annexed
Romagna,
Marche, and the
Duchy of Spoleto, nominally part of the
Papal States. The emperor ordered Enzo to destroy the
Republic of Venice, which had sent some ships against Sicily. In the
Regno itself, Frederick remorselessly purged the clergy of any of Gregory’s supporters: expelling mendicant friars, arresting suspect priests, replacing wavering bishops with loyal supporters, and filling vacant bishoprics with trusted allies. The Sicilian church effectively became independent of Rome and Frederick’s close advisor,
Berard of Castagna, Archbishop of Palermo, was appointed its nominal head. In December of 1239, Frederick entered
Tuscany and spent Christmas in Pisa. In January 1240, Frederick triumphantly entered
Foligno, followed by
Viterbo, whence he aimed to finally conquer Rome to restore the ancient splendours of the Empire. Frederick's plan to attack Rome at that time, however, did not come to fruition as he chose to leave for southern Italy where a papal-incited rebellion flared in Apulia. In southern Italy, Frederick attacked and razed the papal enclaves of
St Angelo and
Benevento. The Emperor remained at the very apex of his power. In the meantime, the pro-Imperial
Ghibelline city of
Ferrara had fallen, and Frederick swept his way northwards, capturing
Ravenna and, after
another long siege,
Faenza. The people of
Forlì, which had kept its Ghibelline stance even after the collapse of
Hohenstaufen power, offered their loyal support during the capture of the rival city: as a sign of gratitude, they were granted an augmentation of the communal coat-of-arms with the Hohenstaufen eagle, together with other privileges. This episode shows how the independent cities used the rivalry between the Empire and the Pope as a means to obtain maximum advantage for themselves. At this time, Gregory considered yielding. A truce occurred, and peace negotiations began. Direct peace negotiations ultimately failed, and Gregory called for a General Council. Frederick and his allies, however, dashed Gregory's plan for a General Council when they intercepted a delegation of prelates travelling to Rome in a Genoese fleet at the crushing
Battle of Giglio (1241), capturing almost all of the high dignitaries and taking thousands of prisoners along with most of the fleet. The emperor proclaimed his victory to be divine judgment and a symbol against the illegality of his persecution by Gregory. Frederick then directed his army toward Rome and the pope, burning and destroying
Umbria as he advanced. Then, just as the Emperor's forces were ready to attack Rome, Gregory died on 22 August 1241. Recognizing that an assault on Rome could prove both unsuccessful and detrimental to broader European perception of his cause, Frederick attempted to show that the war was not directed against the Church of Rome but against the pope by withdrawing his troops and freeing from prison in
Capua two cardinals he had captured at Giglio,
Otto of Tonengo—whom he had befriended and made into a staunch ally—and
James of Pecorara. Frederick then travelled to the
Regno to await the election of a new pope. Even so, his supposedly withdrawal from a direct attack on Rome and the Curia proved a cynical ploy. Based in the south, Frederick proactively interfered in the papal election. During the
sede vacante, the imperial armies continued to surround Rome, blocking the arrival of some cardinal electors known to be hostile to the Emperor’s interests. Unable to reach a consensus, the cardinals were locked in a monastery called the Septasolium by the Roman civic officials, eventually settling on one of their oldest and most feeble members,
Goffredo da Castiglione, in late October 1241. The new pope, Celestine IV, was more amenable to the Imperial cause. However, the conditions within the monastery seemed to have contributed to his death soon after the election the following November. After Celestine IV's death, the war on the peninsula resumed and the cardinals dispersed for over a year and a half before coming together in
Anagni to elect a new pope. The Emperor took advantage of the papal vacancy to press his supremacy across most of Italy, except for some of the hold-out Lombard cities, and refine his newly unified Imperial Italo-Sicilian regime. Frederick was still at the height of his power and his willingness to pointedly prolong the papal election process marked an important milestone. This episode was the first of many protracted
sede vacantes of the later Middle Ages and demonstrated how, during the struggle between empire and papacy, the overt polarization of the latter steadily increased—this culminated in the effective subsuming of the papacy to the French monarchy by the 14th century.
The Mongol Threat In 1241–1242, the forces of the
Mongol Empire decisively defeated the armies of Hungary and Poland and devastated their countryside and all their unfortified settlements. King
Béla IV of Hungary appealed to Frederick for aid, but Frederick, being in dispute with the Hungarian king for some time (as Bela had sided with the papacy against him) and not wanting to commit to a major military expedition so readily, refused. He was unwilling to cross into Hungary, and although he went about unifying his magnates and other monarchs to potentially face a Mongol invasion, he specifically took his vow for the defence of the empire on "this side of the Alps". Frederick was aware of the danger the Mongols posed, and grimly assessed the situation, but also tried to use it as leverage over the papacy to frame himself as the protector of Christendom. While he called them traitorous pagans, Frederick expressed admiration for Mongol military prowess after hearing of their deeds, in particular their able commanders and fierce discipline and obedience, judging the latter to be the greatest source of their success. He called a levy throughout Germany while the Mongols were busy raiding Hungary. In mid-1241, Frederick dispersed his army back to their holdfasts as the Mongols preoccupied themselves with the lands east of the Danube, attempting to smash all Hungarian resistance. He subsequently ordered his vassals to strengthen their defences, adopt a defensive posture, and gather large numbers of crossbowmen. A chronicler reports that Frederick received a demand of submission from
Batu Khan at some time, which he ignored. Frederick II apparently kept himself up to date on the Mongols' activities, as a letter from the emperor dated June 1241 comments that the Mongols were now using looted Hungarian armour. On 20 June in
Faenza, the emperor issued the
Encyclica contra Tartaros, an encyclical letter announcing the
fall of Kiev, the invasion of Hungary and the threat to Germany, and requesting each Christian nation to devote its proper quota of men and arms to the defense of Christendom. According to Matthew of Paris's copy of the encyclical, it was addressed to the Catholic nations—
France,
Spain,
Wales,
Ireland,
England,
Swabia,
Denmark,
Italy,
Burgundy,
Apulia,
Crete,
Cyprus,
Sicily,
Scotland and
Norway—each addressed according to its own national stereotype.
Richard of San Germano states that copies were sent to all the princes of the West and quotes the start of the letter to the French king. In the encyclical, Frederick indicated he had accepted Hungarian submission as emperor. Another letter written by Frederick, found in the Regesta Imperii, dated 20 June 1241, and intended for all his vassals in Swabia, Austria, and Bohemia, included a number of specific military instructions. His forces were to avoid engaging the Mongols in field battles, hoard all food stocks in every fortress and stronghold, and arm all possible levies as well as the general populace. Thomas of Split comments that there was a frenzy of fortifying castles and cities throughout the Holy Roman Empire, including Italy. Either following the Emperor's instructions or on their own initiative,
Frederick II, Duke of Austria, paid to have his border castles strengthened at his own expense. King
Wenceslaus I of Bohemia had every castle strengthened and provisioned, as well as providing soldiers and armaments to monasteries in order to turn them into refuges for the civilian population. Mongol probing attacks materialised on the Holy Roman Empire's border states: a force was repulsed in a skirmish near Kłodzko, 300–700 Mongol troops were killed in a battle near Vienna to 100 Austrian losses (according to the Duke of Austria), and a Mongol raiding party was destroyed by Austrian knights in the district of Theben after being backed to the border of the River March. As the Holy Roman Empire seemed now the target of the Mongols, Frederick II sent letters to
Henry III of England and
Louis IX of France in order to organise a crusade against the Mongol Empire. A full-scale invasion never occurred, as the Mongols spent the next year pillaging Hungary before withdrawing. After the Mongols withdrew from Hungary back to Russia, Frederick turned his attention back towards Italian matters. The danger represented by the presence of the Mongols in Europe was debated again at the
First Council of Lyon in 1245, but Frederick II was excommunicated by that very diet in the context of his struggle with the papacy and ultimately abandoned the possibility of a crusade against the Mongol Empire. == War with the Papacy ==