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Crusading was the fighting of religious wars sanctioned by the Latin Church that began in the medieval period and lasted in various guises for centuries. The Crusades in the eastern Mediterranean aimed at recovering the Holy Land from Muslim rule are the most well known. Crusade as a term is applied to church-sanctioned and even non-religious campaigns fought for a variety of reasons including the suppression of paganism and heresy, the resolution of conflict among rival Roman Catholic groups, or for political and territorial advantage. At the time of the early crusades the word did not exist, and it only later became the leading descriptive term in English.
Pope Urban II preached for the First Crusade in 1095, at the Council of Clermont. He encouraged military support for Emperor Alexios I who needed reinforcements for the Byzantine Empire’s conflict with westward migrating Turks colonising Anatolia. Urban aimed to guarantee pilgrim access to the eastern Mediterranean holy sites under Muslim control. The crusade established four crusader states in the eastern Mediterranean: the County of Edessa, the Principality of Antioch, the Kingdom of Jerusalem and the County of Tripoli. The enthusiastic response to Urban's preaching across all social strata in western Europe established a precedent for further crusades. Volunteers became crusaders by taking a public vow and receiving plenary indulgences from the Church. Some were hoping for a mass ascension into heaven at Jerusalem or God's forgiveness for their sins. Others participated to satisfy feudal obligations, obtain glory and honour, or to seek economic and political gain.
Conventionally an arbitrary system devised by the historian Charles Mills in 1820 is used to number nine distinct campaigns as Crusades. The Second Crusade achieved little beyond the capture of Lisbon. The Third Crusade failed to recapture Jerusalem. The Fourth diverted to sack Constantinople. The Fifth was defeated in Egypt. The Sixth regained Jerusalem by negotiation. The Seventh also ended in defeat in Egypt and the Eighth failed in Tunis. The Ninth is sometimes considered part of the Eighth and is of minor importance, only notable for the presence of Prince Edward, the future king of England. The last of the Eastern Crusader cities fell in 1291 and there were no more crusades to recover the Holy Land. Territorial gains lasted longer in northern and western Europe. Crusades brought all the north-east Baltic and the neighbouring Slavic tribes, known as Wends, under Catholic control in the late 12th century. The French monarchy used the Albigensian Crusade to extend the kingdom to the Mediterranean Sea. The rise of the Ottoman Empire in the late 14th century prompted a Catholic response which led to further defeats at Nicopolis and Varna. In the 15th century the pivotal events in Christian–Islamic relations were marked by two events. The Ottomans capture of Constantinople and the conclusive Spanish victory over the Moors of Granada. The idea of crusading continued, not least in the form of the Knights Hospitaller, until the end of the 18th century.
Modern historians hold widely varying views of crusading. To some, their conduct was incongruous with the stated aims and the implied moral authority of the papacy. Muslims were killed in large numbers on many occasions, as were Christians of other denominations. The crusades had a profound impact on western civilisation. The republics of Genoa and Venice flourished, establishing communes in the Crusader States and expanding trade with eastern markets. Venice gained a maritime Empire. The collective identity of the Latin Church was consolidated under papal leadership by the ideological developments of Crusading and these reinforced the connection between western Christendom, feudalism and militarism. Accounts of crusading heroism, chivalry and piety influenced Medieval romance, philosophy and literature.
The term crusade used in modern historiography at first referred to the wars in the Holy Land beginning in 1095. The range of events to which the term has been applied has been greatly extended, so its use can create a misleading impression of coherence, particularly regarding the early crusades. The Latin terms used for the campaign of the First Crusade were iter, "journey", and peregrinatio, "pilgrimage". The terminology of crusading remained largely indistinguishable from that of Christian pilgrimage during the 12th century. This reflected the reality of the first century of crusading, when not all armed pilgrims fought and not all who fought had taken religious vows. It was not until the late 12th and early 13th centuries that a more specific "language of crusading" emerged. Pope Innocent III used the term negotium crucis or "affair of the cross". Sinibaldo Fieschi, the future Pope Innocent IV, used the terms crux transmarina—"the cross overseas"—for crusades in the Outremer (crusader states) against Muslims and crux cismarina—"the cross this side of the sea"—for crusades in Europe against other enemies of the church. The modern English "crusade" dates to the early 1700s.[A] The term used in modern Arabic, ḥamalāt ṣalībiyya حملات صليبية, lit. "campaigns of the cross", is a loan translation of the term "crusade" as used in western historiography.
French Catholic lawyer Étienne Pasquier, who lived from 1529 to 1615, is thought to be the first historian to attempt the numbering of each crusade in the Holy Land. He suggested there were six. In 1820 Charles Mills wrote History of the Crusades for the Recovery and Possession of the Holy Land in which he counted nine distinct crusades from the First Crusade of 1095–99 to the Ninth Crusade of 1271–72. This convention is often retained for convenience and tradition even though it is a somewhat arbitrary system for what some historians now consider to be seven major and numerous lesser campaigns.
The term "Crusade" may differ in usage depending on the author. In a influential article published in 2001 Giles Constable attempted to define four categories of contemporary crusade study:
- Traditionalists such as Hans Eberhard Mayer restrict their definition of the Crusades to the Christian campaigns in the Holy Land, "either to assist the Christians there or to liberate Jerusalem and the Holy Sepulcher", during 1095–1291.
- Pluralists such as Jonathan Riley-Smith use the term Crusade of any campaign explicitly sanctioned by the reigning Pope. This reflects the view of the Roman Catholic Church (including medieval contemporaries such as Saint Bernard of Clairvaux) that every military campaign given Papal sanction is equally valid as a Crusade, regardless of its cause, justification, or geographic location. This broad definition includes attacks on paganism and heresy such as the Albigensian Crusade, the Northern Crusades, and the Hussite Wars, and wars for political or territorial advantage such as the Aragonese Crusade in Sicily, a Crusade declared by Pope Innocent III against Markward of Anweiler in 1202, one against the Stedingers, several (declared by different popes) against Emperor Frederick II and his sons, two Crusades against opponents of King Henry III of England, and the Christian re-conquest of Iberia.
- Generalists such as Ernst-Dieter Hehl see Crusades as any and all holy wars connected with the Latin Church and fought in defence of the faith.
- Popularists including Paul Alphandery and Etienne Delaruelle limit the Crusades to only those that were characterised by popular groundswells of religious fervour – that is, only the First Crusade and perhaps the People's Crusade.
The use of violence for communal purposes was not alien to early Christians. The evolution of a Christian theology of war was inevitable when Roman citizenship became linked to Christianity and citizens were required to fight against the Empire's enemies. This was supported by the development of a doctrine of holy war dating from the works of the 4th-century theologian Augustine. Augustine maintained that an aggressive war was sinful, but acknowledged a "just war" could be rationalised if it was proclaimed by a legitimate authority such as a king or bishop, was defensive or for the recovery of lands, and a without an excessive degree of violence.
Violent acts were commonly used for dispute resolution in Western Europe, and the papacy attempted to mitigate it. Historians, such as Carl Erdmann, thought the Peace and Truce of God movements restricted conflict between Christians from the 10th century; the influence is apparent in Pope Urban II's speeches. But later historians, such as Marcus Bull, assert that the effectiveness was limited and it had died out by the time of the crusades.
Pope Alexander II developed a system of recruitment via oaths for military resourcing that Gregory VII extended across Europe.  Christian conflict with Muslims on the southern peripheries of Christendom was sponsored by the Church in the 11th century, including the siege of Barbastro and fighting in Sicily In 1074 Gregory VII planned a display of military power to reinforce the principle of papal sovereignty. His vision of a holy war supporting Byzantium against the Seljuks was the first crusade prototype, but lacked support. Theologian Anselm of Lucca took the decisive step towards an authentic crusader ideology, stating that fighting for legitimate purposes could result in the remission of sins.
The first crusade was advocated by Urban II at the Council of Clermont in 1095, promising absolution for the participants' sins. An equivalence was created between crusades for the Holy Land and the Reconquista by Calixtus II in 1123. During the period of the Second Crusade Eugenius III was persuaded by the Cistercian abbot, Bernard of Clairvaux, that the German's conquest of the pagan Slavs was also comparable. The 1146 papal bull Divina dispensatione declared pagan conversion was a goal worthy of crusade. Papal protection, penance and salvation for those killed was extended to participants in the suppression of heretical sects in 1179 during the Third Council of the Lateran.
Elected pope in 1198, Innocent III reshaped the ideology and practice of crusading. He emphasised crusader oaths and penitence, and clarified that the absolution of sins was a gift from God, rather than a reward for the crusaders' sufferings. Taxation to fund crusading was introduced and donation encouraged. In 1199 he was the first pope to deploy the conceptual and legal apparatus developed for crusading to enforce papal rights. With his 1213 bull Quia maior he appealled to all Christians, not just the nobility, offering the possibility of vow redemption without crusading. This set a precedent for trading in spiritual rewards, a practice that scandalised devout Christians and later became one of the causes of the 16th-century Protestant Reformation. From the 1220s crusader privileges were regularly granted to those who fought against heretics, schismatics or Christians the papacy considered non-conformist. When Frederick II's army threatened Rome, Gregory IX used crusading terminology. Rome was seen as the Patrimony of Saint Peter, and canon law regarded crusades as defensive wars to protect theoretical Christian territory.
Innocent IV rationalised crusading ideology on the basis of the Christians' right to ownership. He acknowledged Muslims' land ownership, but emphasised that this was subject to Christ's authority. In the 16th century the rivalry between Catholic monarchs prevented anti-Protestant crusades but individual military actions were rewarded with crusader privileges, including Irish Catholic rebellions against English Protestant rule and the Spanish Armada's attack on Queen Elizabeth I and England.
"Saracen" was a common Greek and Roman term for an Arab Muslim. It was derived from a name used for the nomadic peoples of the Syro-Arabian desert who raided the Syrian region of the Roman Empire. The first English use of "Muslim" is dated to the 17th century. "Franks" and "Latins" were used by the peoples of the Near East during the crusades for western Europeans, distinguishing them from the Byzantine Christians who were known as "Greeks". Crusader sources used the term "Syrians" to describe Arabic speaking Christians who were members of the Greek Orthodox Church, and "Jacobites" for those who were members of the Syrian Orthodox Church
Christianity was adopted throughout the Roman Empire in Late Antiquity. The first Christian Roman Emperor, Constantine the Great, founded the city of Constantinople in 324. In this city the Roman Empire continued until 1453, while the Empire in the west collapsed at the end of the 4th century. The city and the Eastern Roman Empire are more generally known as Byzantium, the name of the older Greek colony it replaced.
Following the foundation of the Islamic religion by Muhammad in the 7th century, and continuing through the 8th century, Muslim Arabs under the Rashidun and Umayyad Caliphates captured Syria, Egypt, and North Africa from the Roman Empire, Sicily and Malta from the Byzantine Empire, Iran from the Sasanian Empire and the majority of Iberia from the Visigothic Kingdom. In 750 a bloody coup brought an end to Umayyad rule to be replaced by the Abbasids and the Islamic state's centre of power moved to Baghdad from Syria, Palestine and Egypt.
The initial phase of Turkic migration into the Middle East saw the intersection of Abbasid and Turkic history from the 9th century. One key driver of Middle Eastern state formation for the following thousand years was the use of slave soldiers. Prisoners from the borderlands of Khurasan and Transoxania were transported to central Islamic lands, converted to Islam and given military training. Known as ghulam or mamluks the theory was, that as slaves they would be more loyal to their masters. In practice it took the Turks only a few decades to make the journey from guard, to commander, governor, dynastic founder and eventually king maker. Political cohesion gradually fragmentated. Examples include the Tulunids in Egypt and Syria (868–905) and the Ikhshidids who followed in Egypt (935–969).
Muslim Iberia (modern Portugal and Spain) established an independent state in the eighth century, divisions between the Shia and Sunni denominations of Islam intensified over the decades and in 969 North Africa broke away under the Fatimids. These were a Shi'ite faction named after Fatima, the daughter of Muhammad. The Fatimids took control of swathes of the Near East including Jerusalem, Damascus and parts of the Mediterranean coastline. The Fatimids asserted their independence from the Sunni Abbasids and had a rival Shi'ite caliph who they considered the successor to Muhammad. From the 8th century, the Christians were campaigning to retake Iberia in what has become known as the Reconquista and from 1060 Norman adventurers began the conquest of the Muslim Emirate of Sicily.
The second wave of Turkish migration saw the arrival of the Seljuk Turks in the 10th century. These were a previously minor ruling clan from Transoxania who had recently converted to Islam and migrated into Iran to seek their fortunes. In the two decades following their arrival they conquered Iran, Iraq and the Near East. The Seljuks and their followers were from the Sunni Islamic tradition which quickly brought them into conflict in Palestine and Syria with the Shi'ite Fatimids.
The recovery of territory by the Byzantine Empire reached its furthest extent in 1025, through the military successes of Emperor Basil II. Its frontiers stretched as far east as Iran. It controlled Bulgaria as well as much of southern Italy and piracy had been suppressed in the Mediterranean Sea. From this point, the arrival of new enemies on all frontiers placed intolerable strains on the resources of the state. In Italy they were confronted by the Normans; to the north, the Pechenegs, the Serbs and the Cumans, as well as the Seljuks to the east. Emperor Romanos IV Diogenes attempted to confront the Seljuks to suppress sporadic raiding; this led to the 1071 defeat of the Byzantine army at the Battle of Manzikert. Once considered a pivotal event by historians, Manzikert is now regarded as only one step in the expansion of the Great Seljuk Empire into Anatolia. This situation was probably the cause of instability in the Byzantine hierarchy rather than the result. To maintain order, the Emperors were forced to recruit mercenary armies, sometimes from the very forces that posed the threat. Yet positive signs of the overall health of the Empire at this time have been identified by recent scholarship.
By the end of the 11th century, the age of Arab-led Islamic territorial expansion was long gone. However, fractious frontier conditions between the Christian and Muslim world remained across the Mediterranean Sea. The territory around Jerusalem had been under Muslim control for more than four centuries. During this time levels of tolerance, trade, and political relationships between the Muslims and the Christians fluctuated. Catholic pilgrims had access to sacred sites and Christian residents in Muslim territories were given dhimmi status on payment of a poll tax, legal rights and legal protection. Indigenous Christians were also allowed to maintain existing churches, and marriages between people of different faiths were not uncommon. The Byzantine Empire and Islamic world were historic centres of wealth, culture and military power. As such, they viewed the West as a backwater that presented little organised threat.
Historical analysis has demonstrated that the First Crusade had its roots in developments earlier in the 11th century but for contemporary Western chroniclers it seems to have been a surprising and unexpected event. The city of Jerusalem had become increasingly recognised by both laity and clerics as symbolic of penitential devotion. There is evidence that segments of the western nobility were willing to accept a doctrine of papal governance in military matters. The Seljuk hold on the holy city was weak and the Byzantines were open to the opportunity presented by western military aid to fight them. This presented the papacy with a chance to reinforce the principle of papal sovereignty with a display of military power such as that proposed by Pope Gregory VII in 1074 but not followed through. Warfare was endemic in Western Europe in this period with violence often a part of political discourse. Contemporaries recognised the moral danger which the papacy attempted to deal with by permitting or even encouraging certain types of warfare. The Christian population had a desire for a more effective church which evidenced itself in rioting in Italy and a greater general level of piety. This prompted investment and growth in monasteries across England, France and Germany. Pilgrimage to the Holy Land began in the 4th century but expanded after safer routes through Hungary developed from 1000. It was an increasingly articulate piety within the knighthood and the developing devotional and penitential practises of the aristocracy that created a fertile ground for crusading appeals. Historians, such as Carl Erdmann, once thought the Peace and Truce of God movements restricting warfare between Christians from the 10th century had an impact. The influence is apparent in Pope Urban's speeches. But later scholars, such as Marcus Bull, assert that the movement's effectiveness was limited and it had already died out by the time of the Crusades. The motivations of the First Crusade also included a "messianism of the poor" inspired by an expected mass ascension into heaven at Jerusalem.
Before the middle of the 11th-century Gregorian Reform, rival Roman noble families and the Holy Roman Emperor competed to control a papacy that amounted to little more than a localised bishopric. Roman families appointed relatives and protégés as popes, while Emperor Henry III invaded Rome and replaced two rival candidates with his nominee. The reforming movement coalesced around Pope Leo IX, intent on abolishing simony and clerical marriage and implementing a college of cardinals responsible for electing future popes. This movement established an assertive, reformist papacy eager to increase its power and influence over secular Europe. A struggle for power developed between Church and state in medieval Europe from around 1075 and continued through the period of the First Crusade. This struggle, now known as the Investiture Controversy, was primarily about whether the Catholic Church or the Holy Roman Empire held the right to appoint church officials and other clerics. To gather military resources for his conflict with the Emperor, Pope Alexander II developed a system of recruitment via oaths that Pope Gregory VII extended into a network across Europe. This also supported the development of a doctrine of holy war developed from the thinking of 4th-century theologian Augustine of Hippo on the treatment of heresy. Death in a just war came to be seen as martyrdom and warfare itself as a penitential activity. Gregory's doctrine of papal primacy led to conflict with eastern Christians whose traditional view was that the pope was only one of the five patriarchs of the church alongside the Patriarchates of Antioch, Constantinople, Alexandria and Jerusalem. In 1054 Leo IX sent a legation to the Patriarch of Constantinople demanded that his supremacy be recognised. The Patriarch responded with an alternative manifesto so the legation excommunicated him. A Synod of the Greek church in turn excommuinicated the legation while condemning the Latin church as heretics in creed and practice leading to a split known as the East–West Schism. There were now two supposedly universal orthodox Christian realms. Where the principle line of division was between a heathen North and a Christian South, now it was between the Catholic West and an Orthodox East.
It was the enmity between the Abbasids and Fatimids that prevented any concerted response to Christian invasion. Power theoretically rested with the respective caliphs in Baghdad and Cairo. In practice executive power was in secular hands: the Sultan in Baghdad and the Vizier in Cairo. The conquered indigenous Arabs had lived under the Seljuks in relative peace and prosperity. In 1092 that relative stability began to disintegrate following the death of the vizier and effective ruler of the Seljuk Empire, Nizam al-Mulk. This was closely followed by the deaths of the Seljuk Sultan Malik-Shah and the Fatimid khalif, Al-Mustansir Billah. Islamic historian Carole Hillenbrand has described this as analogous to the fall of the Iron Curtain in 1989 with the phrase “familiar political entities gave way to disorientation and disunity”. The confusion meant the Islamic world disregarded the world beyond; this caused it to be vulnerable to, and surprised by, the First Crusade.
In 1095 at the Council of Clermont, Pope Urban supported requests from the Byzantine emperor, Alexios I Komnenos for military support in his fighting with the Seljuk Turks. The first response to his preaching was by thousands of predominantly poor Christians in the People's Crusade who indulged in wide-ranging anti-Jewish activities and massacres before being annihilated in a Turkish ambush at the Battle of Civetot. The First Crusade itself was a force led by members of the Western European nobility that, including non-combatants, may have numbered 100,000. Alexios cautiously welcomed them to Byzantium and exacted promises that recovered Byzantine territory would be returned. Nicaea was recaptured before an arduous march across Anatolia. In June 1098 Antioch was captured after an eight-month siege. After a delay of months the army marched along the coast and captured Jerusalem. Many crusaders now considered their pilgrimage complete and returned to Europe. The support of troops from Lorraine enabled Godfrey of Bouillon to take the position of Defender of the Holy Sepulchre. A year later the Lorrainers foiled an attempt by Dagobert of Pisa, the papal legate, to make Jerusalem a theocracy on Godfrey's death. Baldwin I of Jerusalem was chosen as the first Latin king. The limited written evidence available from before 1160 indicates the crusade was barely noticed in the Islamic world. This was probably the result of cultural misunderstanding: the Muslims did not recognise the crusaders as religiously motivated warriors intent on conquest and settlement. They assumed this was the latest in a long line of attacks by Byzantine mercenaries. The Islamic world was divided, with rival rulers in Cairo, Damascus, Aleppo and Baghdad. This gave the crusaders an opportunity for consolidation before a pan-Islamic counter-attack.
Pope Eugenius III called for the Second Crusade in response to the threat presented to the Franks in the Holy Land by the rise of Imad al-Din Zengi, Atabeg of Mosul, and the conquest of the crusader state of Edessa during a general increase in crusading activity, including in the Iberian peninsula and northern Europe. Bernard of Clairvaux spread the message that the loss was the result of sinfulness. Simultaneously, the anti-Semitic preaching of the Cistercian monk, Rudolf, initiated more massacres of Jews in the Rhineland. Zengi was murdered in uncertain circumstances. His elder son Sayf ad-Din succeeded him as atabeg of Mosul while a younger son Nur ad-Din succeeded in Aleppo. The crusade was not a success despite the first campaigning ruling monarchs: Louis VII of France and Conrad III of Germany. The objectives were unclear because Edessa's destruction made its recovery impossible. The French held the Byzantines responsible for defeats by the Seljuks in Anatolia and the Byzantines reiterated claims on future territorial gains. In attacking Damascus, the crusader broke a long period of cooperation between Jerusalem and the city's Seljuk rulers. Bad luck, poor tactics and a feeble five-day siege of the city led to argument, withdrawel by the barons of Jerusalem and retreat. Morale fell, to the anti-Byzantine hostility grew as did distrust between the newly arrived crusaders and those that had made the region their home.
Pope Gregory VIII proposed the Third Crusade after the largest army that Jerusalem had ever put into the field was routed by Saladin at the Battle of Hattin in 1187 and the Crusader states were largely overrun. In 1189 King Guy attempted to recover Acre by besieging the city. Holy Roman Emperor Frederick I drowned in transit to the crusade in Cilicia, but Richard I of England and Philip II of France arrived successfully causing the surrender of the Muslim garrison. While Philip returned to France, Richard recaptured Jaffa and twice advanced to within a day's march of Jerusalem. He recognised the crusaders lacked the resources to capture and hold the city so made a three-year truce gaining pilgrim access to Jerusalem. 
After Pope Innocent III announced the Fourth Crusade on his election in 1198 recruitment was insufficient to pay amount promised to the Venetians for the fleet. For compensation Enrico Dandolo, the Doge of Venice, diverted the crusaders to seize the Christian city of Zara. King Philip of Swabia’s intention was to use the Crusade to restore his exiled brother-in-law, Alexios IV Angelos, to the throne of Byzantium, requiring the overthrow of Alexios III Angelos, the uncle of Alexios IV. The crusaders took Constantinople easily and Alexios III fled. But Alexios IV Angelos was murdered in a violent anti-Latin Byzantine revolt. The crusaders responded by sacking the city in three days of pillaging churches and killing many Greek Orthodox Christians. Many crusaders now lacked the desire for further campaigning and the crusade no longer had the necessary Byzantine logistical support. The result was that the Fourth Crusade never came within 1,000 miles (1,600 km) of its objective of Jerusalem. Instead the Latins increased their territories in the East including Constantinople. The episode demonstrated how poor organisation could wreck an expedition and set a precedent that crusades could legitimately attack not only Muslims but other enemies of the Papacy.
In the 13th century the Mongols defeated the Seljuks and threatened the crusader states while sweeping west from Mongolia through southern Russia, Poland and Hungary. In 1213, Innocent III called for another Crusade at the Fourth Lateran Council. In the papal bull Quia maior he codified existing practice in preaching, recruitment and financing the crusades. The plenary indulgence was defined as forgiveness of the sins confessed to a priest for those who fought in, or even provided funding for, crusades. Geoffrey Chaucer's The Pardoner's Tale may demonstrate a cynical view of vow commutation but it was a pragmatic approach that led to more people taking the cross and raising more money in the following century than in the previous hundred years. Innocent died and in 1217 crusading resumed on the expiration of a number of treaties. The Fifth Crusade consisted of a force—primarily raised from Hungary, Germany, Flanders. This in what is categorised as. The strategy was to attack isolated, easier to defend and self-sufficient Egypt but achieved little. Damietta was captured but when the army advanced into Egypt it was compelled to surrender. Damietta was returned, and an eight-year truce agreed.
Holy Roman Emperor Frederick II was excommunicated for frequently breaking obligations to the crusade but in 1225 he married the [[Isabella II of Jerusalem] giving him a claim to the kingdom of Jerusalem. In 1228 he finally arrived and despite his excommunication by Pope Gregory IX the Sixth Crusade was successful through diplomacy, negotiation and force. Latin Christians were granted most of Jerusalem and a strip of territory that linked the city to Acre. The Muslims controlled their sacred sites and an alliance was made with the Sultan of Egyptbut when Pope Gregory IX attacked his Italian domains he was compelled to return and defend them. The conflict between the Holy Roman Empire and the papacy meant that the responsibility for the f campaigns in the Crusader states often fell to secular such as Theobald I of Navarre and Richard of Cornwall. They led the Barons' Crusade, taking advantage of disunity in Egypt and Syria, combining forceful diplomacy and playing rival factions off against each other. This left a brief and illusive Frankish renaissance. Jerusalem was in Christian hands and with a similar reach to that of the before the battle of Hattin. However, the nobility rejected the accession of the Emperor's son to the throne so could not rely on the Emperor’s resource. Survival depended Ayyubid division, the crusading orders and other western aid for survival. The Mongols displaced the [[Khwārazm-Shāh dynasty|Khwarazmians, who sacked Jerusalem, allied with the Egyptians and destroyed the Frankish-Damascene army at the La Forbie. It was the last tine the crusader states had the resources for a large field army.
Thirteenth century politics in the eastern Mediterranean were complex, with numerous powerful and interested parties. The French were led by the devout Louis IX, king of France, and his ambitiously expansionist brother Charles. In 1249 Louis led the Seventh Crusade’s attacked on Egypt. The crusade was defeated at Mansura and Louis was captured as he retreated. A ten-year truce freed the ransomed Louis and nobles but other prisoners were given a choice between conversion to Islam or death. Between 1265 and 1271 the Franks driven back to a few small coastal outposts. In 1270 Charles diverted his brother Louis IX's and the EightCrusade to Tunis. The crusader army was devastated by disease, and Louis died. Prince Edward, the future king of England, and a small retinue arrived too late for the conflict but continued to the Holy Land in what is known as the Ninth Crusade. Edward survived an assassination attempt, negotiated a ten-year truce, and then returned to manage his affairs in England. This ended the last significant crusading effort in the eastern Mediterranean.
The mainland Crusader states were finally extinguished with the fall of Tripoli in 1289 and Acre in 1291. Ottoman census records of Byzantine churches show that most parishes in the former Crusader states survived at least until 16th-century and remained Christian. The causes of the decline in crusading in the Levant and the failure of the crusader states are multi-faceted. Historians have attempted to explain this in terms of Muslim reunification and jihadi enthusiasm but Thomas Asbridge, amongst others, considers this too simplistic. Muslim unity was sporadic and the desire for jihad ephemeral. The nature of crusading was unsuited to the conquest and defence of the Holy Land. Crusaders were on a personal pilgrimage and usually returned when it was completed. Although the philosophy of crusading changed over time, the crusades continued to be conducted by short-lived armies led by independently minded potentates, rather than centralised leadership. What the crusader states needed were large standing armies. Religious fervour enabled significant feats of military endeavour but proved difficult to direct and control. Succession disputes and dynastic rivalries in Europe, failed harvests and heretical outbreaks, all contributed to reducing Latin Europe's concerns for Jerusalem. Ultimately, even though the fighting was also at the edge of the Islamic world, the huge distances made the mounting of crusades and the maintenance of communications insurmountably difficult. It enabled the Islamic world, under the charismatic leadership of Zengi, Nur al-Din, Saladin, the ruthless Baibars and others, to use the logistical advantages of proximity to victorious effect.
The success of the First Crusade led to further and multifaceted crusading in the Middle Ages. The Western Europeans developed a different, overtly spiritual, perception of the reconquest of the Iberian Peninsula. Other conflicts began to be seen as crusades with crusading privileges and legal frameworks applied. These conflicts outside the Holy Land included the territorial wars in the Baltic, the popes' wars against their political enemies in Italy and, after the Fourth Crusade, the defence of the Latin Empire of Constantinople.
At the time of the First Crusade, Spain had the largest population of Latin Christians living under Muslim rule. The period of Islamic conquest was over by c. 900, and in 1031 the collapse of the Caliphate of Córdoba created the political conditions that would make the Reconquista possible. The Christian powers in Spain had no common identity or shared history based on tribe or ethnicity. As a result, the Kingdom of León, the Kingdom of Navarre and Catalonia united and divided several times in the 11th and 12th centuries. Although small, all had developed a military aristocracy and technique. By the time of the Second Crusade three kingdoms had become powerful enough to embark on the conquest of Islamic territory—Castile and León, Aragon and Catalonia and Portugal. A consensus has emerged among modern historians against the view of a generation of Spanish scholars who believed that a Spanish religious and national victory over Islam was inevitable. In 1123 Pope Calixtus II issued a bull creating an equivalence between the Reconquista and crusading in the east against Muslims. It was during the period of the Second Crusade that the Reconquista was placed within the context of crusading and Pope Eugenius III named Iberia as an objective. The Genoese provided logistic support, a mixed band of crusaders captured Lisbon, which was one of the few Christian victories of the Second Crusade, and Bernard of Clairvaux preached for the campaign in the same terms as he did against the Wends.
In 1212, the Battle of Las Navas de Tolosa was won by the Spanish with the support of 70,000 foreign combatants responding to a crusade preached by Innocent III. Many of the foreigners deserted because of the tolerance the Spanish demonstrated for the defeated Muslims. For the Spanish, the Reconquista was a war of domination rather than a war of extinction. This contrasted with the treatment of the Christians formerly living under Muslim rule, the Mozarabs. The Roman Rite was relentlessly imposed, and the native Christians were absorbed into the mainstream Roman church by the Cistercians, Cluniac clerical appointments and the military orders. The Reconquista continued to attract crusaders and crusader privileges. Al-Andalus, Islamic Spain, was completely suppressed in 1492 when the Emirate of Granada surrendered. At this point the remaining Muslim and Jewish inhabitants were expelled from the peninsula.
Campaigns against heretics and schismaticsEdit
At the Third Council of the Lateran in 1179, Pope Innocent III set a precedent relevant to those crusades that were and are considered as political. In this he encouraged those who suppressed sects considered heretical by the offering of indulgences. One early 13th-century example was the twenty years of campaigning—primarily by French nobility— to suppress a heretical sect called the Cathars in southern France. This is now known as the Albigensian Crusade and is named after the city of Albi, one of the main centres of Catharism. The thirty-year delay in instigating the crusade illustrates a lack of priority given to the campaign in comparison with the more immediate response in crusading rhetoric regarding the papal territorial conflicts in Italy.
The Albigensian Crusade taught the papacy that it was in fact far easier to attack those who tolerated heresy rather than to identify and eradicate the heresy itself. Pressure was exerted on the Commune of Milan because of allegations that the city tolerated Catharism. In Languedoc, feudal lords who failed in its suppression had their lands confiscated and titles forfeited. The historian Norman Housley notes the strong political undertones and connection between heterodoxy and anti-papalism. The pope and the Inquisition would claim that anyone not with them was against them and label opponents as Cathars without requiring evidence. Indulgences were offered to anti-heretical groups such as the Militia of Jesus Christ and the Society of the Blessed Virgin in Milan.
Historians such as Joseph Strayer consider all crusades as political and aimed at the conquest of territory. This is despite numerous papal sponsored holy wars from the 11th century to the 14th century having a rhetorical connection to a spiritual mission. It was not until the end of the 12th century that Innocent IIII became the first pope who deployed the conceptual and legal apparatus developed for crusading to enforce papal rights. The cause was over who would be guardian of the underage Emperor Frederick II. It did set a precedent for political crusades but ultimately achieved nothing.
Gregory IX avoided crusading terminology in the 1230s during his conflict with Frederick II and his Italian supporters, until Frederick threatened to take Rome in 1240. Rome was seen as the Patrimony of St Peter and canon law regarded crusades as defensive wars to protect what was theoretically Christian territory. This was not universally accepted in Christian Europe and there was widespread resistance to clerical taxation to fund these campaigns. Crusading was also unsuitable for these Italian campaigns against the Hohenstaufen. Crusades required clear limitations and firm objectives, but this was a war of attrition. The conflict continued after Frederick II's death when the focus moved to Sicily. Pope Urban IV offered full full crusading indulgences in return for its conquest to Charles of Anjou. In the same year he also offered these to others to campaign in Sardinia and against the Byzantines.
The 1281 election of a French pope, Martin IV, brought the full power of the papacy into line behind Charles. He prepared to launch a crusade against Constantinople but, in what became known as the Sicilian Vespers, an uprising fomented by the Byzantine Emperor Michael VIII proclaimed Peter III of Aragon as king of Sicily depriving Charles of the resources of the island. In response, Martin excommunicated Peter and called for an Aragonese Crusade, which was unsuccessful.
Pagans in the NorthEdit
In 1147, the papacy began to describe the wars waged by Scandinavian and German Christians against the pagans in the Baltic coastal region as crusades. Bernard of Clairvaux persuaded Pope Eugenius III that the conflict with the Wends was a holy war analogous to the Reconquista, even though the Germans were more motivated by wars of territorial conquest than events in the east. This Wendish Crusade saw Saxons, Danes, and Poles begin to forcibly convert the neighbouring tribes of Polabian Slavs or "Wends". This, and further campaigns against Estonian and Finnish pagans were understood in religious terms by contemporaries as a struggle against paganism. The theoretical justification, however, was weak without the argument that the crusaders were fighting to reclaim Christian territory.
Military orders played a controversial role in the Baltic, most notably the Teutonic Knights who were founded in Palestine after the Siege of Acre in the 1190s and modelled on the Templars. A precedent for the knights had already been set by the Livonian Brothers of the Sword and the Order of Dobrzyń who were founded to defend Riga and German commercial interests. The Teutonic Knights' strong links to German imperium diverted efforts from the Holy Land to Prussia and Livonia. The order conducted harsh and brutal suppression of the local populations, including Orthodox Christians. In this way Latin control was extended 300 miles (480 kilometres) to the east in the 13th century. Historian Robert Bartlett defines the conquest and organisation of power in the Baltic as part of a general movement for 'the expansion of Latin Christendom'. It was made possible by the crusading ideology placing the full machinery of the Church behind superior military technology. It enabled the recruitment of troops via preaching, the offer of spiritual rewards for combatants and the administrative machinery to establish government in the conquered territories.
Europe saw popular outbursts of ecstatic piety in support of the crusades, such as that resulting in the Children's Crusade in 1212. Large groups of young adults and children spontaneously gathered, believing their innocence would enable success where their elders had failed. Few, if any at all, journeyed to the eastern Mediterranean. Although little reliable evidence survives for these events, they provide an indication of how hearts and minds could be engaged for the cause.
Late medieval and early modern crusadesEdit
Minor Crusading efforts lingered into the 14th century, and several Crusades were launched during the 14th and 15th centuries to counter the expansion of the Ottoman conquest of the Balkans. In 1309 as many as 30,000 peasants gathered from England, north-eastern France, and Germany proceeded as far as Avignon but disbanded there. Peter I of Cyprus captured and sacked Alexandria in 1365 in what became known as the Alexandrian Crusade; his motivation was as much commercial as religious. Louis II led the 1390 Barbary Crusade against Muslim pirates in North Africa; after a ten-week siege, the Crusaders signed a ten-year truce.
After their victory at the Battle of Kosovo in 1389, the Ottomans had conquered most of the Balkans, and had reduced Byzantine influence to the area immediately surrounding Constantinople, which they later proceeded to besiege. In 1393 the Bulgarian Tsar Ivan Shishman had lost Nicopolis to the Ottomans. In 1394 Pope Boniface IX proclaimed a new Crusade against the Turks, although the Western Schism had split the papacy. This Crusade was led by Sigismund of Luxemburg, King of Hungary; many French nobles joined Sigismund's forces, including the Crusade's military leader, John the Fearless (son of the Duke of Burgundy). Sigismund advised the Crusaders to focus on defence when they reached the Danube, but they besieged the city of Nicopolis. The Ottomans defeated them in the Battle of Nicopolis on 25 September, capturing 3,000 prisoners.
The Hussite Wars, also known as the Hussite Crusade, involved military action against the Bohemian Reformation in the Kingdom of Bohemia and the followers of early Czech church reformer Jan Hus, who was burned at the stake in 1415. Crusades were declared five times during that period: in 1420, 1421, 1422, 1427, and 1431. These expeditions forced the Hussite forces, who disagreed on many doctrinal points, to unite to drive out the invaders. The wars ended in 1436 with the ratification of the compromise Compacts of Basel by the Church and the Hussites.
As the Ottomans pressed westward, Sultan Murad II destroyed the last Papal-funded Crusade at Varna on the Black Sea in 1444 and four years later crushed the last Hungarian expedition. John Hunyadi and Giovanni da Capistrano organised a 1456 Crusade to lift the Siege of Belgrade. Æneas Sylvius and John of Capistrano preached the Crusade, the princes of the Holy Roman Empire in the Diets of Ratisbon and Frankfurt promised assistance, and a league was formed between Venice, Florence, and Milan, but nothing eventually came of it. In April 1487 Pope Innocent VIII called for a Crusade against the Waldensians of Savoy, the Piedmont, and the Dauphiné in southern France and northern Italy. The only efforts undertaken were in the Dauphiné, resulting in little change. Venice was the only polity to continue to pose a significant threat to the Ottomans in the Mediterranean, but it pursued the "Crusade" mostly for its commercial interests, leading to the protracted Ottoman–Venetian Wars, which continued, with interruptions, until 1718. The final end of the Crusades, in an at least nominal effort of Catholic Europe against Muslim incursion, comes in the 16th century, when the Franco-Imperial wars assumed continental proportions. Francis I of France sought allies from all quarters, including from German Protestant princes and Muslims. Amongst these, he entered into one of the capitulations of the Ottoman Empire with Suleiman the Magnificent while making common cause with Hayreddin Barbarossa and a number of the Sultan's North African vassals.
Latin rule in GreeceEdit
The conquest of Christian Constantinople by the Fourth Crusade created a significant increase in the Frankish crusader presence in the eastern Mediterranean. Those crusaders that remained established control over the city, Thrace, Greece, the extreme north west of Anatolia as well as the Ionian and Aegean Islands. A council of six Venetians and six Franks selected Count Baldwin of Flanders as a new Latin Emperor. This established a Latin Empire in the east and partitioned the Byzantine territory. Venice gained a maritime domain including one-eighth of Constantinople, Istria, Dalmatia, Albania, Negroponte, the Kingdom of the Morea, the Aegean islands of the Duchy of the Archipelago, the islands of Crete and the Kingdom of Candia.
The Venetians endured a long standing conflict with the Ottoman Empire until the final possessions were lost in the Seventh Ottoman–Venetian War in the 18th century. This period of Greek history is known as the Frankokratia or Latinokratia ("Frankish or Latin rule") and designates a period when Catholic western European nobles, primarily from France and Italy, ruled over the Orthodox Byzantine Greeks on former Byzantine territory.
The crusaders' propensity to follow the customs of their Western European homelands meant that there were very few innovations developed from the culture in the crusader states. Three notable exceptions to this are the military orders, warfare and fortifications. The Knights Hospitaller, formally the Order of Knights of the Hospital of Saint John of Jerusalem, were founded in Jerusalem before the First Crusade but added a martial element to their ongoing medical functions to become a much larger military order. In this way the knighthood entered the previously monastic and ecclesiastical sphere.
Military orders like the Knights Hospitaller and Knights Templar provided Latin Christendom's first professional armies in support of the Kingdom of Jerusalem and the other crusader states. The Templars, formally the Poor Fellow-Soldiers of Christ and the Temple of Solomon, and their Temple of Solomon were founded around 1119 by a small band of knights who dedicated themselves to protecting pilgrims en route to Jerusalem. The Hospitallers and the Templars became supranational organisations as papal support led to rich donations of land and revenue across Europe. This, in turn, led to a steady flow of new recruits and the wealth to maintain multiple fortifications in the crusader states. In time, they developed into autonomous powers in the region. After the fall of Acre the Hospitallers first relocated to Cyprus, then conquered and ruled Rhodes (1309–1522) and Malta (1530–1798), and continue in existence to the present-day. King Philip IV of France probably had financial and political reasons to oppose the Knights Templar, which led to him exerting pressure on Pope Clement V. The pope responded in 1312, with a series of papal bulls including Vox in excelso and Ad providam that dissolved the order on the alleged and probably false grounds of sodomy, magic and heresy.
The Kingdom of Jerusalem was the first experiment in European colonialism, setting up the Outremer as a "Europe Overseas". The raising, transportation, and supply of large armies led to flourishing trade between Europe and the Outremer. The Italian city-states of Genoa and Venice flourished, planting profitable trading colonies in the eastern Mediterranean. The crusades consolidated the papal leadership of the Latin Church, reinforcing the link between Western Christendom, feudalism, and militarism and increased the tolerance of the clergy for violence. Muslim libraries contained classical Greek and Roman texts that allowed Europe to rediscover pre-Christian philosophy, science and medicine. The growth of the system of indulgences became a catalyst for the Reformation in the early 16th century. The crusades also had a role in the formation and institutionalisation of the military and the Dominican orders as well as of the Medieval Inquisition.
The behaviour of the crusaders in the eastern Mediterranean area appalled the Greeks and Muslims, creating a lasting barrier between the Latin world and the Islamic and Orthodox religions. This became an obstacle to the reunification of the Christian church and fostered a perception of Westerners as defeated aggressors. Many historians argue that the interaction between the western Christian and Islamic cultures played a significant, ultimately positive, part in the development of European civilisation and the Renaissance. Relations between Europeans and the Islamic world, stretched across the entire length of the Mediterranean Sea, led to an improved perception of Islamic culture in the West. But this broad area of interaction also makes it difficult for historians to identify the specific sources of cultural cross-fertilisation.
Historical parallelism and the tradition of drawing inspiration from the Middle Ages have become keystones of political Islam encouraging ideas of a modern jihad and long struggle while secular Arab nationalism highlights the role of western imperialism. Muslim thinkers, politicians and historians have drawn parallels between the crusades and modern political developments such as the mandates given for the governance of Syria, Lebanon, Palestine, and Israel by the United Nations. Right-wing circles in the Western world have drawn opposing parallels, considering Christianity to be under an Islamic religious and demographic threat that is analogous to the situation at the time of the crusades. Crusader symbols and anti-Islamic rhetoric are presented as an appropriate response, even if only for propaganda purposes. These symbols and rhetoric are used to provide a religious justification and inspiration for a struggle against a religious enemy. Some historians, such as Thomas F. Madden, argue that modern tensions are the result of a constructed view of the crusades created by colonial powers in the 19th century and transmitted into Arab nationalism. For him the crusades are a medieval phenomenon in which the crusaders were engaged in a defensive war on behalf of their co-religionists.
Originally, medieval understanding of the crusades was narrowly focussed on a limited set of interrelated texts, most notably Gesta Francorum which possibly dates from as early as 1099. This created a papalist, northern French and Benedictine template for later works. These all demonstrated a degree of martial advocacy that attributed both success and failure to God's will. This clerical view was soon challenged by vernacular adventure stories based on the work of Albert of Aachen. The historian William of Tyre expanded on Albert's writing in his Historia. Completed by 1200, William's work describes the warrior state the Outremer had become through the tensions between the providential and secular. Medieval crusade historiography remained more interested in presenting moralistic lessons than information, extolling the crusades as a moral exemplar and a cultural norm.
Attitudes toward the crusades during the Reformation were shaped by the radical fragmentation of religious orthodoxy, the perceived threat of the Ottomans and the French Wars of Religion. Protestant martyrist John Foxe in his History of the Turks (1566) blamed the sins of the Roman church for the failure of the crusades. He also condemned the use of crusades against those he considered had maintained the faith, such as the Albigensians and Waldensians. Lutheran scholar Matthew Dresser (1536–1607) extended this view. The crusaders were lauded for their faith but Urban II's motivation was seen as part of his conflict with German Emperor Henry IV. On this view, the crusade was flawed, and the idea of restoring the physical Holy Places was "detestable superstition". Pasquier highlighted the failures of the crusades and the damage that religious conflict had inflicted on France and the church. He lists victims of papal aggression, sale of indulgences, church abuses, corruption, and conflicts at home.
Age of Enlightenment philosopher historians such as David Hume, Voltaire and Edward Gibbon used crusading as a conceptual tool to critique religion, civilisation and cultural mores. For them the positives effects of crusading, such as the increasing liberty that municipalities were able to purchase from feudal lords, were only by-products. This view was then criticised in the 19th century by crusade enthusiasts as being unnecessarily hostile to, and ignorant of, the crusades. Alternatively, Claude Fleury and Gottfried Wilhelm Leibniz proposed that the crusades were one stage in the improvement of European Civilisation; that paradigm was further developed by Rationalists.
In France the idea that the crusades were an important part of national history and identity continued to evolve. In academic circles the phrase “Holy War” was the main descriptor, but the more neutral terms kreuzzug from German and the French croisade became established. The word "crusade" entered the English language in the 18th century as a hybrid from Spanish, French and Latin. Gibbon followed Thomas Fuller in dismissing the concept that the crusades were a legitimate defence as they were disproportionate to the threat presented. Palestine was an objective, not because of reason but because of fanaticism and superstition.
William Robertson expanded on Fleury in a new, empirical, objective approach placing crusading in a narrative of progress towards modernity. The cultural consequences of growth in trade, the rise of the Italian cities and progress are elaborated in his work. In this he influenced his student Walter Scott. Jonathan Riley-Smith considers that much of the popular understanding of the crusades derives from the 19th century novels of Scott and the French histories by Joseph François Michaud.
The Muslim world exhibited little interest in European culture until the 16th century and in the crusades until the middle of the 19th century. There was no history of the crusades translated into Arabic until 1865 and no published work by a Muslim until 1899. In the late 19th century, Arabic-speaking Syrian Christians began translating French histories into Arabic, leading to the replacement of the term "wars of the Ifranj" – Franks – with al-hurub al Salabiyya – wars of the Cross. Namık Kemal published the first modern Saladin biography in 1872. The Jerusalem visit in 1898 of Kaiser Wilhelm prompted further interest, with Sayyid Ali al-Hariri producing the first Arabic history of the crusades.
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