When historians have considered Frederick ii and the crusades, they have mainly paid attention to his bloodless recovery of Jerusalem in 1229.Footnote ¹ A decade later he became the first emperor to be the target of a crusade himself, but, while there is a huge literature on his conflict with the papacy, its crusading features are usually overlooked or mentioned only in passing.Footnote ² That partly derives from the traditional perception that crusades against Christians were abuses rather than an integral part of crusading. It is only in the last few decades that a pluralist approach has taken on a momentum that does not associate crusading with any particular location or enemy.Footnote ³

Among the themes still waiting to be explored, the impact of the crusade against Frederick in northern Italy looms large. It was the first substantial crusade fought within that area, which was traditionally the main battleground for conflicts between empire and papacy. It was also where they overlapped with conflicts between emperors and cities, among the cities and within cities, all of which played a fundamental role in shaping the Italian city republics. How did the crusade against Frederick ii compare with previous experiences, to what extent was it implemented, what were its consequences and how was it perceived in northern Italy? Here again the state of research is the same, which, in a vicious circle, has probably something to do with the general impression that the crusade against Frederick ii achieved very little.Footnote ⁴ The literature on the political crusades has focused on other topics, such as their origins, Innocent iii and southern Italy.Footnote ⁵ Rebecca Rist's recent work studied the point of view of the papacy.Footnote ⁶ Norman Housley's seminal work on the Italian crusades concentrated on the period after the death of Frederick ii in 1250.Footnote ⁷

This paper aims to tackle these questions by studying prose historical works which were produced in the Po Valley, where the Lombard League was active, by authors who lived or were born during the reign of Frederick ii. It will place passages referring to crusading practices in their textual, historical, social and biographical contexts, and compare them to other sources. These works are a relatively rich and diverse body that offers an invaluable window onto how the introduction of political crusades affected the city states: they are mostly city-centric but come from different parts of the region and of the century; some took pro-papal and others pro-imperial stances; moreover, they differ from sources from the rest of Christendom in that many of their authors were lay members of the urban elite or officials of the communal governments.Footnote ⁸

Before tackling the crusade against Frederick that followed his excommunication in 1239, it is crucial to consider its closest quasi-crusade antecedents, that is, the so-called War of the Keys of 1228–30 and a number of other northern Italian episodes in the 1230s.

The so-called War of the Keys was the first crisis between Frederick and Gregory ix. It led to an invasion of southern Italy that was sustained by tithes and troops from across Europe.Footnote ⁹ The invasion took place after Frederick had set out for the Holy Land, but upon his return he repelled it, and by 1230 he had reached a settlement with the pope. Lombard cities were involved in this episode and some Lombard historical works covered it.

Papal correspondence on that crisis (including that with the Lombard cities) featured themes that closely resembled those of the later crusade, but did not fully portray it as a crusade. Gregory ix underlined how those who opposed the emperor supported the Church (‘in ecclesie servitis’), described the invasion as the business of the Church (‘negotio ecclesie’) and the invading forces as the army of the Church (‘exercitus ecclesie’).Footnote ¹⁰ In March 1228 the pope threatened to treat Frederick as a heretic, and around August he drew a parallel between Frederick and the main heretical groups of that time by renewing their excommunications concurrently.Footnote ¹¹ Gregory eventually also promised remission from sins for those who fought against the emperor (including the Lombard cities), but only when the military campaign was practically lost; if that move had aimed to reverse the tide, it failed.Footnote ¹²

Since the last stages of the pontificate of Honorius iii, the papacy had been acting as arbiter in the conflict that had recently started between Frederick and the Lombard League, but during the War of the Keys it asked and received the help of the League, albeit on a relatively small scale.Footnote ¹³ None of the proceedings of the League regarding the War of the Keys survive, but the Dictamina rhetorica by the teacher of rhetoric Guido Faba (d. c. 1245) contains exchanges in which its rectors remind the members of the League of their pledge to send knights ‘in support of the Church’ (‘ad ecclesie subsidium’) and ‘in reverence to God and to the Holy Roman Church as well as for the protection of the league’ (‘pro reverentia Dei sancteque Romane ecclesie nec non et pro totius societatis statu’).Footnote ¹⁴ It is safe to assume that such exchanges were verisimilar didactic exercises.Footnote ¹⁵ Yet the Dictamina rhetorica was produced around 1230 and Faba himself came from Bologna, which was a consistent member of the League.Footnote ¹⁶

Historical works did not portray the War of the Keys as a crusade either. Most notably, Richard of San Germano (d. c. 1243), a southern Italian member of Frederick's court, called the papal forces ‘clavigeri’, that is, bearers of St Peter's keys (hence the name frequently attached to the conflict), rather than ‘crucesignati’, as he represented, and with a clear polemical intent, Frederick's victorious forces upon his return from the Holy Land.Footnote ¹⁷

Of the main Lombard works that covered the crisis, two displayed anti-imperial preferences and were produced before the crusade against Frederick, but there is also a later pro-imperial work that reported on that crusade as well. The first two, the so-called Annales placentini guelfi and the Chronicon faventinum, covered the period until 1235 and 1236 respectively. Their leanings are very clear and matched those of their cities, which were consistent members of the League. The author of the relevant portion of the Chronicon faventinum was possibly a cathedral canon, but that of the Annales placentini guelfi was the notary Giovanni Codagnello, who was close to his commune and campaigned for the restoration of the League in 1226.Footnote ¹⁸ The pro-imperial work is the so-called Annales placentini gibellini, whose intentionally anonymous author, probably a clerk close to the pro-imperial Landi family, covered the period until 1284 much more subtly than his compatriot.Footnote ¹⁹ The titles by which these works are known can be misleading: the Placentine annals are much more substantial and complex than the Faentine chronicle.Footnote ²⁰

The Chronicon faventinum identified with the League and wished to underline its support and that of Faenza for the Church on that occasion. It twice briefly mentioned that Faenza sent twenty-seven knights to Apulia with the rest of ‘our Lombard League’ (‘cum aliis de nostra societate Lombardorum’) ‘in the service of the pope’ (‘in servicium domini pape’).Footnote ²¹

Codagnello displayed a very similar attitude, but his work is one of the more informative sources on the War of the Keys, reflecting the themes of the papal letters and Faba's models, but ignoring offers of remissions of sins. He blamed the crisis on the damage that Frederick's delays in setting out for the Holy Land had caused to those who travelled to Apulia, and highlighted how the emperor and his representatives reacted to the resulting threat of excommunication by invading ‘possessiones et iura’ of the Roman Church, which revealed his intention to destroy it and bring desolation to the whole of Italy. This was a clear reference to the common interests of the League and the papacy. Codagnello then identified two further stages in the papal response, stating that they were both based on the counsel of wise men, both lay and clerical. First the pope excommunicated Frederick and labelled him a heretic (‘eundem excommunicatum et hereticum denotando’), which shows that Codagnello took literally, and perhaps exaggerated, the slightly more subtle parallel between Frederick and heretics drawn by Gregory. Then, ‘when the pope saw that the spiritual sword had no tangible effects against the wickedness of the emperor’, he requested the help of the faithful of the Roman Church, whose duty was to defend its rights and possessions (‘auxilium a sancte Romane ecclesie fidelibus postulavit’). The sentence that followed was probably Codagnello's comment: ‘it seems righteous and proper to oppose the arrogant in order to stop him from deploying his arrogance’ (‘Iustum enim et ydoneum videtur resistere superbo ne possit superbiam suam exercere’). The focus then turns to Lombardy, reporting how the pope summoned the help of the League, which pledged troops. On one occasion Piacenza sent thirty-six knights (roughly like Faenza), but there were delays. This matches complaints found in the papal correspondence and the tone of Faba's exchanges. Codagnello, however, overlooked the outcome of the crisis: the next reference to the empire and the papacy was to the negotiations between Frederick and the League of 1232, in which Gregory resumed his role as arbiter even though the League eagerly reminded him of their common interests.Footnote ²²

Codagnello was one of the main sources of the Annales placentini gibellini, but the latter's account of the War of the Keys is different. The author of the annals did not describe it as a crusade either, as he did with the conflict against Frederick after his excommunication in 1239, which suggests an awareness of the difference between them. Yet the annals did not directly criticise Frederick, who plays quite a passive role in them: the pope blamed him for the delays of the crusade and excommunicated him, but Frederick sailed to the Holy Land none the less because he wanted to fulfil the orders of the pope; during his absence ‘it seemed to the pope’ (‘videbatur domno pape’) that imperial vicars were attacking possessions of the Church, which led to the invasion of southern Italy, supported by the League and other troops. The annals did address the outcome of the crisis, but only by stating that the ‘milites Ecclesie’ retreated upon Frederick's return, and that a rapprochement with the pope followed.Footnote ²³ Overall, the Annales placentini gibellini portrayed Frederick more as a victim of a crisis caused partly by events beyond his control and partly by the pope.

Other far less well-known quasi-crusade episodes took place in northern Italy in the 1230s. One involved Ezzelino da Romano, a lord who later became one of Frederick's closest allies and, after the emperor's death, the target of a crusade that enjoyed an exceptional response and an influential legacy.Footnote ²⁴ In 1231 Gregory ix offered a three-year indulgence to those who fought against him, and remission from all sins in case of death, specifically citing the Paduans (Ezzelino's local enemies and members of the League), whom he called ‘speciales Christi athletae’ for their record against heretics and their support of the libertas Ecclesie.Footnote ²⁵ Ezzelino was accused of heresy and of sheltering heretics (his family was already notorious for this, and was involved in disputes with local churches).Footnote ²⁶ At the end of 1233 the pope also granted a one-year indulgence and remission from sins in case of death to those who fought heretics at Milan.Footnote ²⁷ Milan was the leader of the League, but had also a very bad reputation for heresy.Footnote ²⁸ The Franciscans were involved in both cases, led in Milan by Leone da Perego, who later played an important role in crusading practices against Frederick ii.Footnote ²⁹ To those episodes the creation of militant lay confraternities should be added, the Militia of Jesus Christ, founded at Parma in 1233, being the best example.Footnote ³⁰

What has just been listed was the most crusade-like, but also the least thriving, side of the campaign against heresy and lay encroachment on the libertas Ecclesie that peaked in northern Italy under Gregory ix. Interventions in city statutes and the activity of the mendicant orders and of the inquisition were far more prominent, and, while heresy and politics were already inextricably intermingled, the scale and consequences of that phenomenon were not as significant as they came to be a decade later.Footnote ³¹ These quasi-crusade episodes have left no further trace, and no historical work mentioned them, including those that came to demonise Ezzelino and thus gave birth to his well-known black legend, which focused rather on the crusades that were launched against him after Frederick's death.Footnote ³² The same applies to confraternities: if the Militia of Jesus Christ was meant to become a regional network, it never took off, not even at Parma, as the Parmese Franciscan Salimbene de Adam (c. 1221–87, but did not begin writing until 1283) noted.Footnote ³³

Moreover, Frederick had little to do with these episodes. The papal struggle against heretics and for the libertas Ecclesie in the 1230s touched members of the League as well as imperial supporters, whose response was not dissimilar in an overall lack of enthusiasm.Footnote ³⁴ The papacy might have favoured members of the League, or pushed some cities towards the League, but in other cases its intervention had the opposite effect.Footnote ³⁵ Despite their lingering and mounting tensions, papacy and empire were at peace and ostensibly collaborating. Thus in 1231 Gregory asked Frederick not to damage their joint efforts against heresy by using force against the Lombards, which would have given respite to the many heretics of that region.Footnote ³⁶ Yet Frederick increasingly played the heresy card against his Lombard opponents autonomously, and it was his use of force, leading to his crushing victory at Cortenuova in 1237, that played a determining role in precipitating the new crisis with the papacy in 1239.Footnote ³⁷

Ezzelino is a good case in point regarding the fluidity of the 1230s. His black legend has often overshadowed the fact that, following his family tradition, he did not initially support Frederick.Footnote ³⁸ When the pope offered indulgences against him he was actually closer to the League, which a couple of months later accepted him as a member. We do not know whether he had made peace with the papacy by then (he was absolved from excommunication in 1233), but his heretical reputation and any papal sanctions are absent from the surviving evidence of the debate that his application to the League caused.Footnote ³⁹ For that debate the only evidence is the lone surviving pro-Ezzelino historical work, a panegyric that Gerardo Maurisio of Vicenza, a lay member of Ezzelino's circle and his envoy to the League, produced in the late 1230s.Footnote ⁴⁰ Maurisio completely ignored Ezzelino's problems with the papacy and overemphasised his family's crusading tradition.Footnote ⁴¹ He even stated that the League immediately adopted his petition to threaten Padua (a recent recipient of Gregory's praise) with expulsion from the League if it continued to harass Ezzelino in his quarrel with the bishop of Feltre, which was probably the source of one of Ezzelino's problems with the Church; the League's subsequent siding with Ezzelino's enemies pushed him towards Frederick, who took him under his protection in 1232.Footnote ⁴² Ironically, Ezzelino's switch of allegiance was crucial in breaking the League's control over the Alpine passes, which allowed Frederick to take military action.

These two quasi-crusade elements combined after Frederick's excommunication in 1239. Unfortunately Codagnello's comprehensive account of the War of the Keys is unmatched among works on the new conflict, which, however, attributed unambiguous crusade features to it.

In his Chronica civitatis ianuensis, written at the end of the century, when he was archbishop of Genoa, Jacobus de Varagine, who had entered the Dominican order during Frederick's reign, stated that the Romans ‘cruce signati fuerunt’ when Gregory ix solicited them to defend Rome against the approaching Frederick in 1240, the result being that the emperor changed his plans.Footnote ⁴³ The Annales placentini gibellini also noted that event, citing the same reasons and consequences, and adding that Gregory's preaching included a poignant display of and an appeal to the relics of SS. Peter and Paul that convinced ‘the majority of the Romans’ to ‘lift the symbol of the cross in defence of the Church’.Footnote ⁴⁴ That occurrence must have had a profound impact upon the collective memory: around 1300, on the other side of northern Italy, the notary Riccobaldo da Ferrara (who was born during Frederick's reign, in the 1240s) mentioned it too.Footnote ⁴⁵ According to a German chronicle, in 1297 Boniface viii referred to it during his conflict against the Colonna, and expected his Roman audience to know about it.Footnote ⁴⁶

Papal and imperial letters as well as a biography of Gregory ix confirm these testimonies. The pope incited Christians to follow the example of the Romans, mentioning the offer of general indulgences, and how crosses received from the pope's hands were placed on their shoulders, which shows that the crusade was not merely a local incident.Footnote ⁴⁷ An imperial encyclical from March 1240 referred to Gregory's exhortation to take the cross against Frederick, attributing it to the pope's desperation.Footnote ⁴⁸

The appeal of February 1240 can be taken as the start of the crusade, triggered by Frederick's strength and threat to take over Rome despite his excommunication. As Genoese and Venetian works testify, that appeal was immediately implemented at Genoa and Ferrara. Together with Milan, these were at that time the hotspots of the conflict in northern Italy.

The annals of Genoa are probably the most helpful source regarding the implementation of the crusade in northern Italy, for several reasons. Unlike de Varagine's later work, these annals did not mention events in Rome in February 1240, and preferred to focus on local developments. Yet they equated the crusade that resulted from those events to ‘traditional’ ones, reporting the arrival in Genoa of the papal legate Gregorio de Romana in the spring of 1240, who preached the crusade against the enemies and rebels of the Church by offering a remission from all sins that was equal to that issued for the Holy Land.Footnote ⁴⁹ De Varagine, in turn, later ignored this episode. The annals then also mentioned that in 1242 Genoese forces wore crosses on their shoulders against a vast array of imperial and pro-imperial enemies.Footnote ⁵⁰ Moreover, these annals are the best example of official historical works in Communal Italy, and, unique among those considered here, they were produced in the 1240s, authored by a committee from the city's chancellery.Footnote ⁵¹ Crusading interests had been a distinctive feature of Genoese historiography since its very inception.Footnote ⁵²

The reference to crusade preaching at Genoa in 1240 did not specify who the enemies were, and the entry for 1242 shows that they included Genoa's local opponents. The annals did not mention Frederick's excommunication in 1239 either, but they clearly took it for granted, together with the reasons for what they described as his ‘guerra maxima’ with the Church.Footnote ⁵³ The entry of 1239 rather focused on clashes within Genoa and with neighbours, and mentioned the capture of letters showing that they, and some Genoese factions, were in league with Frederick, called here emperor ‘dictus’, the typical mode of address for an excommunicate.Footnote ⁵⁴ Those confrontations increased from 1240, when Genoa came to be at the centre of the preparations for a council that Gregory ix called in order to deal with the situation. In spring 1241 a Pisan-Sicilian fleet, under the command of a renegade Genoese captain, inflicted a disastrous defeat upon the Genoese convoy carrying representatives and financial aid to Rome for the council. Some accounts attribute crusade trappings to that event.Footnote ⁵⁵ Not the Genoese annals though, although the campaigns of 1242 were Genoa's response to that disgraceful defeat.Footnote ⁵⁶

The inextricable mingling of shifting local, regional and wider conflicts, and the deterioration of relations with Frederick, with Genoa pressed on all sides, is the underlying theme of this section of the annals, which displays what can only be described as a siege mentality.Footnote ⁵⁷ Another theme is the bond with the papacy, with which Genoa struck an agreement in 1238. Yet it is only after the report of crusade preaching that the annals repeatedly portrayed Genoa as a champion of the Church, which they associated with the defence of the patria.Footnote ⁵⁸ Rather than a chance record, therefore, the report of crusade preaching was inserted because it fitted into the official narrative of the ruling elite, reflecting its concerns and self-representation in the 1240s by providing an ideological foundation for its conflicts.

Concurrent with events in Genoa, the crusade was pursued on the other side of northern Italy against the pro-imperial city of Ferrara (January to June 1240), as a passage from the work of Martino Canal (written between 1267 and 1275) suggests. He was a clerk of the Venetian republic, possibly close to Doge Rainero Zeno (d. 1268).Footnote ⁵⁹ Martino recounted that when the crusade against Ezzelino was preached in Venice in 1256, the doge pointed to the precedent of Venetian participation, in service to the Church, in the campaigns in Syria and the conquests of Tyre, Constantinople and Ferrara.Footnote ⁶⁰ As at Genoa, the bond with the papacy is a major theme in Canal's work and in wider Venetian self-representation in the second half of the century.Footnote ⁶¹

Canal's testimony is not only significant for its pluralist position towards the crusades, but also because, while scholarship has not devoted particular attention to the siege of Ferrara, it attracted a truly exceptional interest among medieval works across and beyond northern Italy.Footnote ⁶² It was the first large operation against the pro-imperial party in northern Italy since Cortenuova and Frederick's excommunication in 1239, and the numerous actors involved partly explain its coverage. Moreover, Ferrara loomed large in the ‘war of the chanceries’ between Frederick and Gregory ix, which touched all Christendom.Footnote ⁶³ This included the famous encyclical Ascendit de mare bestia of June 1239, which only named Ferrara in the ‘terra Ecclesie in Lombardiam’ that Frederick had allegedly occupied, while Frederick described it as a ‘civitas imperii’.Footnote ⁶⁴

It is intriguing that the other works did not instantly attribute obvious crusading features to the siege, but various clues confirm that they were there. The interpretative key is provided by the Genoese annals. Genoa was not even involved in the siege, but the annals, in an unusual foray into the other side of Italy, reported it in the sentence that immediately followed that on Gregorio de Romania's preaching at Genoa, describing the besiegers as ‘coadiutores ecclesie’ and attributing a leading role to the papal legate Gregorio da Montelongo.Footnote ⁶⁵ Likewise, a letter from Montelongo to the Ferraresi, included in Guido Faba's Epistole, from the early 1240s, states that they had brought God's wrath upon themselves when they sided with persecutors of the Christian faith. It exhorted them to return to God's fold and to follow the precepts of the Church, threatening to place the symbol of the cross upon the faithful, whose virtues would have thrown chaos among the enemies of Christ and taken by storm any heretical depravity.Footnote ⁶⁶ In the light of that evidence other testimonies fall into place. The Annales placentini gibellini and the Annales S. Iustinae patavini, for example, attributed a leading role to Montelongo too, the first mentioning the siege after his crusading activities at Milan, and the second stating that the deed was done ‘pro ecclesia’.Footnote ⁶⁷ Canal's work attributed the siege to the will of the papacy, and stated that the city was handed over to Montelongo.Footnote ⁶⁸

The outcome of the siege of Ferrara had momentous long-term consequences locally, confirming papal claims, paving the way for the Este's later signoria, which lasted until the sixteenth century, and assuring Venetian control of the Po, the main trade route of northern Italy.Footnote ⁶⁹

On the regional level, apart from extensive participation by the anti-imperial front, the siege sent shockwaves through the pro-imperial one. According to the Placentine annals, at Cremona, Parma, Reggio Emilia and Modena it caused a quarrel between those who wanted to send help and those who were against it; no help was sent in the end, and Frederick started to despise those who had refused it.Footnote ⁷⁰ Those cities, and especially Parma, soon saw the formation of groups that came to be identified with the pars ecclesie.Footnote ⁷¹

Yet the impact of that siege was even wider. According to the English Matthew Paris (d. 1259) it opened up the military side of the clash between emperor and pope, brought devastation and massacres, and such a use of the ‘gladius materialis’ by a papal legate, together with his cruel and merciless treatment of the defeated, astonished clerics across Christendom, causing fear and anxiety for the wider consequences of those actions, and of the conflict between empire and papacy, upon the Church and Christian society as a whole.Footnote ⁷² Siberry's seminal work on criticism of crusading did not consider that passage, probably because it does not bear any obvious crusading references, but it challenges the suggestion that English criticism of internal crusades was mainly based on financial reasons.Footnote ⁷³ Indeed, Matthew mentioned the siege twice (wrongly in 1239 and then in 1240), and in between he reported the unwillingness of English crusaders to allow papal cavils to redirect them towards shedding Christian blood in Italy.Footnote ⁷⁴

Despite their abundant coverage of the siege, Italian sources were much more cautious in their assessment of its consequences, and many ignored them altogether. At the very best they mentioned the treachery used to seize Ferrara, and the Placentine annals rather attributed the expulsion of imperial supporters to the marquis of Este.Footnote ⁷⁵ For a more vocal testimony one has to wait for the local Riccobaldo, who highlighted the persecutions that forced thousands into exile.Footnote ⁷⁶ Actually, between Matthew Paris and the Placentine annals, Rolandino of Padua (a notary who worked for his commune and taught rhetoric at the local studium) underlined how fairly treated the Ferraresi and their properties were on that occasion.Footnote ⁷⁷ Was he being ironic, or was he offsetting his, rather balanced, take on the similar fate that his own city later experienced at the hands of ‘hii qui vobiscum crucem Domini baiulabant’? The quotation comes from Rolandino's fictional dialogue between Ezzelino and the papal legate who lead the crusade against him in the mid 1250s.Footnote ⁷⁸ He was Philip of Pistoia, who had played a significant role at the siege of Ferrara when he was bishop there, but on the side of the attackers. Rolandino publicly read his work (known as the Chronica of the Trevisan March, but in reality a history of the rise and fall of Ezzelino) in post-Ezzelino Padua in 1262, where the studium approved it. The anti-Ezzelino narrative had become crucial to local identity.Footnote ⁷⁹

At times the beginning of the crusade against Frederick has rather been placed in 1239. The apocalyptic language that Gregory employed after Frederick's excommunication did recall that of Innocent iii's crusades.Footnote ⁸⁰ Allusions comparing the struggle against Frederick with crusades fought in various theatres can be found between March 1239 and February 1240. Yet in 1239 no equivalent of the papal appeal of 1240 can be found, and the only evidence of the implementation of crusade practices before 1240 would come from Milan.

The Annales placentini gibellini reported Frederick's excommunication in March and copied a papal letter announcing it to the archbishop of Milan and his suffragans, which did not refer to any crusade. Yet the lines that followed stated that the pope sent Montelongo to Milan, who, arriving in April, and, ‘having the citizens taken up the symbol of the cross on his mandate and prepared two banners displaying the cross and the keys’, attacked the pro-imperial city of Lodi.Footnote ⁸¹ This work mentioned the taking of the cross by the Romans in 1240 in a later passage.

Unfortunately, the only other thirteenth-century historical work that paid substantial attention to Montelongo at Milan in that period is the Annales Sanctae Iustinae patavini. This was produced by an anonymous cleric between 1289 and 1293 without reporting obvious crusading practices. The author only stated that the pope knew by experience that if Frederick conquered Lombardy he would oppress the Church too. Thus he excommunicated the emperor and sent Montelongo to Milan, where he strenuously supported the ‘fideles ecclesie’ against Frederick, enflaming the fledging will of the Milanese and their allies to fight for freedom.Footnote ⁸²

On the other hand, the Milanese Dominican Galvano Fiamma (d. 1344) expanded upon the Placentine annals. He recounted that, upon Frederick's excommunication, the pope sent two legates to preach the cross against him, Jacopo da Pecorara to France and Montelongo to Milan, so that ‘per totum mundum praedicatur crux contra ipsum sicut contra saracinum’. Fiamma then confirmed that Montelongo's preaching galvanised the Milanese, who took the cross in countless numbers when Frederick attacked them in late 1239.Footnote ⁸³

Supporting evidence also comes from an imperial encyclical of March 1240. It stated that the pope had made himself war leader and temporal prince of Milan, joining the Lombard rebels and appointing as prefects of the Milanese/papal army Montelongo and Leone da Perego, who falsely attired themselves as knights and offered absolution from all sins against him.Footnote ⁸⁴ There are obvious parallels with the Placentine annals: if the Milanese used banners with St Peter's keys and a papal legate led them, then it was plausible to call them ‘papalis exercitus’.

The evidence attesting crusading practices before 1240, however, should be taken cautiously. Fiamma produced his work a century later, and, although he used sources now lost, he also generously added fourteenth-century inventions.Footnote ⁸⁵ By then the political crusades had a long history, and Fiamma witnessed that against the Visconti, after which he joined their entourage.Footnote ⁸⁶ He often betrays the intent of legitimising their rule, and his emphasis on the crusading pedigree of the city in the service of the papacy might have served to counterbalance recent events. The thirteenth-century evidence is entirely from imperial or pro-imperial sources produced after the events in Rome in 1240. Frederick embellished the role of Montelongo, probably misleadingly comparing Milan to Ferrara, because there is no evidence that Gregory claimed temporal authority over Milan. In 1239 Frederick had not mentioned spiritual rewards when he criticised Henry iii of England for allowing the collection of cash that was used for Milanese ‘stipendiarios milites’.Footnote ⁸⁷

It is therefore possible that those sources retrospectively overplayed the crusading features of the Milanese events of 1239, and it is probable that they were at best advanced experimentations, which built upon what Gregory ix had left in 1229–33 (the use of St Peter's keys suggests a link).Footnote ⁸⁸ Montelongo's own initiative needs to be considered too: in September 1239 the clergymen who were trying to broker a peace stated that he tried to undermine allegiance to the emperor in any way he could (‘modis omnibus quibus potest’).Footnote ⁸⁹

The mission of Jacobus of Pecorara to France, which, according to Fiamma, mirrored that of Montelongo, provides a useful counterpart. When, in 1239, Gregory ix announced the mission to Louis ix, he exhorted the king to follow the example of the deeds done in defence of the Church under his predecessors, mentioning the Holy Land, Constantinople and the Albigensian crusade. Yet that letter did not cite crusading benefits, and it fell on deaf ears.Footnote ⁹⁰

In 1239 the pope was probably still testing the waters, uncertain whether to take so controversial a measure as launching a full crusade against the emperor and his Lombard supporters. While the feedback that he received from north of the Alps was poor, the results at Milan were very encouraging. The Roman event of 1240 certainly helped to complete the transition to a full crusade, but it might also have been influenced by Montelongo's success at Milan: in both cases Frederick was repelled from crucial cities. Immediately after the Roman appeal of 1240, Montelongo moved from Milan to the siege of Ferrara with Milanese forces.Footnote ⁹¹

While historical works reported crusading practices around 1240, they are seemingly absent from their accounts of the rest of Frederick's reign, including those on Ezzelino's black legend, despite the emphasis that Innocent iv placed on the crusade.Footnote ⁹² Many works seemingly ignored them altogether, including two of the more complex ones, that is, those of Rolandino da Padua and Salimbene de Adam, both of whom were pro-papal (Salimbene indeed saw Frederick as the embodiment of the AntiChrist).Footnote ⁹³

That poor coverage could have reflected the low prominence of the crusade features, but it is possible that historical works took them for granted and encapsulated them in the way that they labelled Frederick's opponents as pars, fideles, or coadiutores ecclesie. After all, the defence of the Church was what the crusade was about, and, albeit not as popular among scholars as terms that centred upon pilgrimage or the cross, phrases relating to the Church and its defence were commonly employed to refer to crusades.Footnote ⁹⁴ That applies to crusades to the Holy Land too: in 1239 English crusaders described their forthcoming mission as ‘expedicionem ecclesie sancte Dei’.Footnote ⁹⁵

Indeed, the earliest appearances of those labels for Lombard factions coincide with the opening references to the crusade. The Genoese annals first mentioned ‘coadiutores ecclesie’ with regard to the siege of Ferrara.Footnote ⁹⁶ The same entry called the League for the first time ‘societas Lombardorum ecclesie fidelium’, while reporting its betrayal by Alessandria in contempt for the reverence for God and the Roman Church. Until then those annals had called it ‘societas Lombardie’ or simply ‘Lombardi’. The Annales Sanctae Iustinae patavini first referred to Lombard ‘fideles ecclesie’ regarding Milan and its allies, that is, the League, in relation to Montelongo's activity at Milan.Footnote ⁹⁷

Other works point in the same direction. Salimbene, for example, provided a list of pro-papal and pro-imperial factions in northern Italy.Footnote ⁹⁸ Yet the earliest in that list was certainly that of Paolo Traversari ‘ex parte ecclesie’ at Ravenna, which, as a whole, supported Frederick until June 1239, then took part in the siege of Ferrara, where Paolo played an important role. Frederick recaptured Ferrara in August 1240, shortly after Paolo's death.Footnote ⁹⁹ When Jacobo da Varagine mentioned the peace in 1295 between the Genoese ‘Mascarati sive gibellini’ and ‘Rampini sive guelfi’, he stated that their quarrel had lasted ‘per annos LV et amplius’.Footnote ¹⁰⁰ Factions existed at Genoa before 1240, but those mentioned by Jacobo fully crystallised in the early 1240s.Footnote ¹⁰¹ Local annals first mentioned a ‘pars ecclesie civitatis parme’ in 1245 (which had been a consistent imperial supporter, but in 1248 was the setting of a disastrous imperial defeat) and that was the first ‘pars ecclesie’ mentioned by Rolandino.Footnote ¹⁰²

By comparison, Codagnello's reference to the ‘fideles ecclesie’ during the War of the Keys was a general call to all the faithful.Footnote ¹⁰³ He clearly highlighted the strong links between the League and the papacy, but, as was the rule before 1240, he only called it ‘societas Lombardie’, and never intrinsically identified it with the Church.Footnote ¹⁰⁴ Indeed, before 1240 the opponent of the pars imperii was the societas Lombardie, not a Lombard pars ecclesie, as the work of Rolandino and the Genoese annals regarding events around 1236 testify.Footnote ¹⁰⁵

Codagnello's work covered the twelfth century too, and more, and the same lack of formal identification of the League, or city factions, with the Church applies to the rest of his work, including his account of the conflict between the League, the papacy and Frederick Barbarossa. Barbarossa's opponents had equally fought for the libertas ecclesie, while for Pope Alexander iii the Lombards were inspired by the Holy Spirit, and he threatened interdicts and excommunications against defectors. Yet there had been no offer of indulgences and no taking of the cross then.Footnote ¹⁰⁶

Institutional changes on the ground fully substantiate those chronological coordinates. On the regional level, the League had provided ad hoc and limited help in the War of the Keys, and had not supported the quasi crusade against Ezzelino. Yet the renewal of the oath of the League of December 1239 was the last trace of the rectors of the League and the first to feature a constitutional pledge to follow the precepts of the Church, which matches the interpretation of 1239 as a year of transition. In their place, the following records (from winter 1240–1) attributed a presiding role to a papal legate, described its members as ‘adherentes ecclesie’ and ‘ecclesie filii bellatores strenui’, and specified that its scope was to keep up the ‘honour’ of its members and that of the Roman Church, all of which was previously unknown.Footnote ¹⁰⁷ On the local level, statutes against Frederick's supporters, labelled as infedeles and equated to heretics, appeared in the 1240s.Footnote ¹⁰⁸ Yet the first reference to imperial supporters as ‘inimici ecclesie’ that I could find in local statutes comes from the treaty that, in the aftermath of the siege of Ferrara, Bologna and Ferrara struck at the request of Montelongo in 1240.Footnote ¹⁰⁹

It is possible that the militant confraternities for the laity founded in the 1230s provided some inspiration for the coadiutores ecclesie of the 1240s, but they had largely been isolated events, and there is no evidence of links between the two phenomena in northern Italy, not even at Parma, which is the best-documented case.Footnote ¹¹⁰ The crusade against Frederick actually succeeded where the campaigns of the 1230s had failed, in creating a regional network devoted to the cause of the papacy. Yet an already existing structure, that is, the League, had to be modified for that, and it did not become a religious confraternity, and nor did the local partes ecclesie. The second half of the century saw a new flourishing of interconnected confraternities that backed pro-papal factions within cities.Footnote ¹¹¹ That might have actually built on the climate of opinion that the crusade against Frederick created, where support for the papacy had become more mainstream and factional strife had further increased in intensity.

The existence of pro-papal factions in the Italian cities is a traditional theme in scholarship, but their first patent identification with the papacy, suggesting that it had become a distinctive feature, has not been connected with the crusade against Frederick. At the very best Frederick's reign as a whole, or the period after Cortenuova, have been pointed to.Footnote ¹¹² More generally, scholarship has used labels such as guelf (used in the Po Valley from the late thirteenth century), and more rarely pars ecclesie, to discuss developments throughout the central Middle Ages, even when they were unknown to primary sources.Footnote ¹¹³ This is not to deny the increasing polarisation of factions, the connections between the papacy and some of them, or that terms such as guelf and ghibellines are convenient shortcuts. Nevertheless, the use of those labels has hindered an appreciation of the impact of the crusade against Frederick in northern Italy.

The political situation in central-northern Italy, especially at Milan and at Rome around 1240, brought the final introduction of full-blown crusades to northern Italy, but that political situation also played a determining role in shaping the consequences of that development. By 1239 the League was a shadow of its former self, its few remaining members surrounded by imperial and pro-imperial forces, and its resources, morale and identity severely battered. The entrance of the papacy into the conflict represented a vital opening and this time the introduction of penitential warfare provided an effective extra boost. The anti-imperial front embraced the crusade, gaining new vigour and strong leadership with Gregorio da Montelongo, which helped to stem imperial ascendancy. On the other hand, partly because of the weaknesses of the anti-imperial front, its identity and structure were transformed by the crusade both at the regional and the local level, and that was probably its most profound and longest lasting impact. After all, contrary to the War of the Keys, to which the League had pledged troops for a far away campaign, the crusade against Frederick and his allies was fought inside northern Italy, where its bearing was not even remotely comparable to that of the isolated quasi-crusades of the 1230s. It also penetrated deep within the cities, adding to factional strife a religious dimension on a previously unknown scale. That was a very considerable change, and the chronic features that the conflict soon acquired, together with its prolongation with the papal-Angevin alliance and the following political crusades, helped to consolidate it in the long-term. Local developments should be added too, such as the consequences of the siege of Ferrara. In other words, the impact upon northern Italy of the crusade against Frederick ii was far greater than hitherto assumed, and indeed a momentous one.

Historical works are crucial in tracing the tentative introduction and escalation of the early political crusades in northern Italy, especially in the light of the scarcity of papal evidence about it, at least for the pontificate of Gregory ix. However, it was quite surprising to find the most direct references to them in works produced by laymen, whose general lack of direct comments or criticism is intriguing, given their diverse backgrounds. True, with the crusade against Frederick pro-papal attitudes seem to have become a topos in northern Italian works. Many of them were produced at the time of the papal-Angevin alliance, but not the Genoese contemporary annals, which were the most helpful source for this enquiry. It is no wonder, therefore, that they adopted what scholarship would call a pluralist approach. Genoese and Venetian works might have also been influenced by the long immersion of their cities in the history of the crusades. Yet only hints of criticism can be found in the few pro-imperial works too, which were very restrained indeed. The case of the siege of Ferrara, however, leaves one wondering whether that lack of comment or criticism was due, at least partially, to censorship and self-censorship.Footnote ¹¹⁴