The Crusades were military campaigns sanctioned by the Latin Catholic Church during the High Middle Ages through to the end of the Late Middle Ages. In 1095 Pope Urban II proclaimed the first crusade, with the stated goal of restoring Christian access to the holy places in and near Jerusalem. Many historians and some of those involved at the time, like Saint Bernard of Clairvaux, give equal precedence to other papal-sanctioned military campaigns undertaken for a variety of religious, economic, and political reasons, such as the Albigensian Crusade, the Aragonese Crusade, the Reconquista, and the Northern Crusades. Following the first crusade there was an intermittent 200-year struggle for control of the Holy Land, with six more major crusades and numerous minor ones. In 1291, the conflict ended in failure with the fall of the last Christian stronghold in the Holy Land at Acre, after which Catholic Europe mounted no further coherent response in the east.
Some historians see the Crusades as part of a purely defensive war against the expansion of Islam in the near east, some see them as part of long-running conflict at the frontiers of Europe and others see them as confident aggressive papal led expansion attempts by Western Christendom. The Byzantines had been contesting for centuries for territory in the region with mixed success in the Arab–Byzantine Wars, the Byzantine–Seljuq Wars and in 1071 had lost the sparsely occupied plains of Anatolia after their defeat by the Seljuk Turks at the Battle of Manzikert. Urban II sought to reunite the Christian church under his leadership by providing Emperor Alexios I with military support. Several hundred thousand soldiers became Crusaders by taking vows and by receiving plenary indulgences. These crusaders were Christians from all over Western Europe under feudal rather than unified command, and the politics were often complicated to the point of intra-faith competition leading to alliances between combatants of different faiths against their coreligionists, such as the Christian alliance with the Islamic Sultanate of Rûm during the Fifth Crusade.
The impact of the Crusades was profound and judgement of the conduct of Crusaders has varied widely from highly critical to laudatory. Jonathan Riley-Smith identifies the independent states established, such as the Kingdom of Jerusalem and the Crusader States, as the first experiments in "Europe Overseas". These ventures reopened the Mediterranean to trade and travel, enabling Genoa and Venice to flourish. Crusading armies would engage in commerce with the local populations while on the march, with Byzantine emperors often organizing markets for Crusader forces moving through their territory. The crusading movement consolidated the collective identity of the Latin Church under the Pope’s leadership and was the source of heroism, chivalry, and medieval piety. This in turn spawned medieval romance, philosophy, and literature. However, the crusades reinforced the connection between Western Christendom, feudalism, and militarism that ran counter to the Peace and Truce of God that Urban had promoted. The crusaders often pillaged the countries through which they travelled in the typical medieval manner. Nobles often retained much of the territory gained rather than returning it to the Byzantines as they had sworn to do. Encouraged by the Church, the Peoples' Crusade prompted the Rhineland massacres and the massacre of thousands of Jews. In the late 19th century this episode was used by Jewish historians to support Zionism. The Fourth Crusade resulted in the sacking of Constantinople, effectively ending the chance of reuniting the Christian church by reconciling the East–West Schism and leading to the weakening and eventual fall of the Byzantine Empire to the Ottomans. Nevertheless, some crusaders were only poor people trying to escape the hardships of medieval life in an armed pilgrimage leading to Apotheosis at Jerusalem.
- 1 Terminology
- 2 Historiography
- 3 Background
- 4 Role of women, children, and class
- 5 Outremer
- 6 Crusading Decline
- 7 Military Orders
- 8 Legacy
- 9 Age of Crusade
- 9.1 Reconquista (718–1492)
- 9.2 People's Crusade (1096)
- 9.3 First Crusade (1095–1099) and immediate aftermath
- 9.4 Second Crusade (1147–1149)
- 9.5 Wendish (1147–1162)
- 9.6 Third Crusade (1187–1192)
- 9.7 Northern crusades (1193–1290)
- 9.8 German Crusade (1195–1198)
- 9.9 Fourth Crusade (1202–1204)
- 9.10 Albigensian Crusade (1208–1241)
- 9.11 Fifth Crusade (1217–1221)
- 9.12 Sixth Crusade (1228–1229)
- 9.13 Seventh Crusade (1248–1254)
- 9.14 Eighth and Ninth Crusade (1270–1272)
- 9.15 Aragonese Crusade (1284-1285)
- 9.16 Crusades of the 15th century
- 10 See also
- 11 References
- 12 Bibliography
- 13 External links
"Crusade" is a modern term, from the French croisade and Spanish cruzada, that was applied to the medieval military expeditions only in retrospect. The French form of the word first appears in the L'Histoire des Croisades written by A. de Clermont and published in 1638. By 1750, the various forms of the word "crusade" had established themselves in English, French, and German. The Oxford English Dictionary records its first use in English as occurring in 1757 by William Shenstone.
The crusades were never referred to as such by their participants. The original crusaders were known by various terms, including fideles Sancti Petri (the faithful of Saint Peter) or milites Christi (knights of Christ).
Like pilgrims, each crusader swore a vow (a votus) to be fulfilled on successfully reaching Jerusalem, and they were granted a cloth cross (crux) to be sewn into their clothes. This "taking of the cross", the crux, eventually became associated with the entire journey. They saw themselves as undertaking an iter, a journey, or a peregrinatio, an armed pilgrimage. The inspiration for this “messianism of the poor" was the expected mass apotheosis at Jerusalem.
Historians consider that between 1096 and 1291 there were seven major crusades and numerous minor ones. However, some consider the Fifth Crusade of Frederick II as two distinct crusades. This would make the crusade launched by Louis IX in 1270 the Eighth Crusade. In addition, sometimes even this Crusade is considered as two, leading to a Ninth Crusade.
A pluralist view of the Crusades has developed in the 20th century inclusive of all papal-led efforts, whether in the Middle East or in Europe. This takes into account the view of the Latin Church and medieval contemporaries such as Saint Bernard of Clairvaux that gave equal precedence to comparable military campaigns against pagans, heretics and many undertaken for political reasons. This wider definition includes the persecution of heretics in Southern France, the political conflict between Christians in Sicily, the Christian re-conquest of Spain and the conquest of heathens in the Baltic. Countering this is the view the Crusades were a defensive war in the Middle East against Muslims to free the Holy Land from Muslim rule.
Popes frequently called crusades for political reasons and crusades were also declared as a means of conflict resolution amongst fellow Christians. Pope Innocent III declared a crusade against his political opponent Markward of Anweiler in Sicily. Only a few people took part, and the need for the crusade ended in 1202 when Markward died. This is generally considered the first "political crusade" Between 1232 and 1234 there was a crusade against the Stedingers, peasants who refused to pay tithes to the Archbishop of Bremen. The archbishop excommunicated them, and Pope Gregory IX declared a crusade in 1232. The peasants lost the Battle with Altenesch on 27 May 1234 and were destroyed. Emperor Frederick II was the object of several political crusades called by a number of popes. In 1240 Pope Gregory IX deposed and preached a crusade against him for his opposition in Italy. In 1248 Pope Innocent IV's crusade against him was transferred in 1250 to his son, Conrad IV when he died to little effect. Crusades were called against Frederick's illegitimate son Manfred, King of Sicily, from 1255 through 1266, and Conrad's son, Conradin, in 1268 with the urging of Charles of Anjou. Two crusades appear to have been called against opponents of King Henry III of England – one from 1215 to 1217 and the other from 1263 to 1265 with the first enjoying the same privileges as those given to crusaders on the Fifth Crusade. The second got as far as having papal legates being dispatched to England with the power to declare a crusade against Simon de Montfort, but Montfort's death in 1265 ended this. The Norwich Crusade of 1383, also called the Despenser's crusade, which was a military expedition that aimed to assist the city of Ghent in its struggle against the supporters of Antipope Clement VII was really an extension of the Hundred Years War, rather than a purely religious enterprise.
Before the 16th century the words "Muslim" and "Islam" were very rarely used by europeans. During the crusades the term widely used for Muslim was Saracen. In Greek and Latin this term had a longer evolution from the beginning of the first millennia where it referred to a people who lived in desert areas around the Roman province of Arabia who were distinguished from Arabs. The term developed to include Arab tribes and by the 12th century had become an ethnic and religious marker synonymous with "Muslim" in Medieval Latin literature.  In the romance The King of Tars, Saracens are black-skinned while Christians are lighter-skinned. The Old French 11th century heroic poem The Song of Roland takes the association of black skin with Saracens a step further by making it their only exotic feature.
The term Frank has been used by many of the Eastern Orthodox and Muslim neighbours of medieval Latin Christendom (and beyond, such as in Asia) as a general synonym for a European from Western and Central Europe, areas that followed the Latin rites of Christianity under the authority of the Pope in Rome. Another term with similar use was "Latins".
Modern historians often refer to Christians following the Latin rites in the eastern Mediterranean as "Franks" or "Latins", regardless of their country of origin, whereas they use the words Rhomaios and Rûmi ('Roman') for Orthodox Christians. On a number of Greek islands, Catholics are still referred to as Φράγκοι (Frangoi) or 'Franks', for instance on Syros, where they are called Φραγκοσυριανός (Frangosyrianos). Latin Christians living in the Middle East (particularly in the Levant) are known as Franco-Levantines.
During the Mongol Empire in the 13-14th centuries, the Mongols used the term 'Franks' to designate Europeans. The term Frangistan ("Land of the Franks") was used by Muslims to refer to Christian Europe and was commonly used over several centuries in Iran and the Ottoman Empire.
Examples of derived words include:
- Frangos in Greek
- Frenk in Turkish
- al-Faranj, Afranj and Firinjīyah in Arabic
- Farang, Farangī in Persian
- Pfirangi in Sanskrit
During the Reformation and Counter-Reformation of the 16th century, historians saw the Crusades through the prism of their own religious beliefs. Protestants saw them as a manifestation of the evils of the Papacy, while Catholics viewed the movement as a force for good. During the Enlightenment, historians tended to view both the Crusades and the entire Middle Ages as the efforts of barbarian cultures driven by fanaticism. By the 19th century, with the dawning of Romanticism, this harsh view of the Crusades and its time period was mitigated somewhat, with later 19th-century crusade scholarship focusing on increasing specialization of study and more detailed works on subjects.
Enlightenment scholars in the 18th century and modern historians in the West have expressed moral outrage at the conduct of the crusaders. In the 1950s, Sir Steven Runciman wrote that "High ideals were besmirched by cruelty and greed ... the Holy War was nothing more than a long act of intolerance in the name of God".
In the 20th century, three important works covering the entire history of the crusades have been published, those of Rene Grousset, Steven Runciman, and the multi-author work edited by K. M. Stetton. A pluralist view of the Crusades has developed in the 20th century inclusive of all papal-led efforts, whether in the Middle East or in Europe. Historian Thomas Madden has made the contrary argument that "[t]he crusade, first and foremost, was a war against Muslims for the defense of the Christian faith.... They began as a result of a Muslim conquest of Christian territories." Madden says the goal of Pope Urban was that "[t]he Christians of the East must be free from the brutal and humiliating conditions of Muslim rule."
Byzantium & The Near East
After 636, when Muslim forces defeated the Eastern Roman/Byzantines at the Battle of Yarmouk, the control of Palestine passed through the Umayyad Dynasty, the Abbasid Dynasty, and the Fatimids. Toleration, trade, and political relationships between the Arabs and the Christian states of Europe ebbed and flowed until 1072 when the Fatimids lost control of Palestine to the rapidly expanding Great Seljuq Empire. For example, the Fatimid Caliph al-Hakim bi-Amr Allah ordered the destruction of the Church of the Holy Sepulchre, only to have his successor allow the Byzantine Empire to rebuild it. The Muslim rulers allowed pilgrimages by Christians to the holy sites. Resident Christians were considered people of the book and so were tolerated as Dhimmi, and inter-marriage was not uncommon. Cultures and creeds coexisted as much as competed, but the frontier conditions were not conducive to Latin Christian pilgrims and merchants. The disruption of pilgrimages by conquering Seljuq Turks prompted support for the Crusades in Western Europe.
The Byzantine Empire was resurgent from the end of the 10th century, with Basil II spending most of his 50-year reign on campaign, conquering a great amount of territory. He left a growing treasury, at the expense of neglecting domestic affairs and also ignoring the cost of incorporating his conquests into the Byzantine Ecumene. None of Basil’s successors had any particular military or political talent, and governing the Empire increasingly fell into the hands of the civil service. Their efforts to spend the Byzantine economy back into prosperity only resulted in burgeoning inflation. To balance the increasingly unstable budget, Basil’s large standing army was dismissed as unnecessary, and native thematic troops were cashiered and replaced by foreign mercenaries. Following the defeat of the Byzantine army at the Battle of Manzikert in 1071, the Seljuq Turks had taken over almost all of Anatolia, and the Empire descended into frequent civil wars.
The Latin Church
In the West an aggressive and reformist Papacy came into conflict with both the Eastern Empire and Western secular monarchs, leading to the East-West Schism in 1054 and the Investiture Controversy, which had started around 1075 and was still on-going during the First Crusade. The papacy began to assert its independence from secular rulers, marshaling arguments for the proper use of armed force by Christians. The result was intense Christian piety, interest in religious affairs, and religious propaganda advocating "Just War" in order to retake Palestine from the Muslims. Taking part in such a war was seen as a form of penance, which could remit sins. Meanwhile in Europe, the Germans were expanding at the expense of the Slavs, while Sicily was conquered by the Norman adventurer Robert Guiscard in 1072.
Council of Clermont
In 1074 the Byzantine Emperor Michael VII sent a request for military aid to Pope Gregory VII, but although Gregory appears to have considered leading an expedition to aid Michael, nothing reached the planning stage. The Eastern Empire faced difficulties in the Danube river area, as the Pechenegs had allied with the Seljuq Turks and threatened the Empire until 1091, when they were defeated by Emperor Alexios I Komnenos.
In 1095 Alexios sent envoys to the west requesting military assistance against the Seljuqs. Alexios needed to reinforce his tagmata, so the embassy probably sought to recruit mercenaries and may have exaggerated the dangers facing the Eastern Empire in order to secure the needed troops. The message was received by Pope Urban II at the Council of Piacenza. In November Urban called the Council of Clermont to discuss the matter, further urging the bishops and abbots whom he addressed directly to bring with them the prominent lords in their provinces. The Council lasted from 19 to 28 November, attended by nearly 300 clerics from throughout France. Urban discussed the Cluniac reforms of the Church and extended the excommunication of Philip I of France. Urban spoke for the first time about the problems in the east on 27 November, promoting the struggle of western Christians against the Muslims who had occupied the Holy Land and were attacking the Eastern Roman Empire. There are six main sources of information on the Council: the anonymous Gesta Francorum ("The Deeds of the Franks" dated c. 1100/1101), which influenced all versions of the speech, except that by Fulcher of Chartres who was present at the council; Robert the Monk, who may have been present; as well as Baldric, archbishop of Dol, and Guibert de Nogent, who were not present at the council. All the accounts were written much later following different literary traditions and differ greatly.
Robert the Monk, in Historia Iherosolimitana, written in 1106/7, reports that Urban called for orthodoxy, reform, and submission to the Church. Robert records that the pope asked western Christians, poor and rich, to come to the aid of the Byzantine Empire because "Deus vult," ("God wills it"). Robert records that Urban promised remission of sins for those who went to the east, although the 'Liber Lamberti', a source based on the notes of Bishop Lambert of Arras, who attended the Council, indicates that Urban offered the remission of all penance due from sins, later called an indulgence. Robert account has Urban delivering a classical battle speech: he emphasizes reconquering the Holy Land more than aiding the Greeks; the intervening decades and the events of the First Crusade had certainly shifted the emphasis. According to Robert, Urban listed various gruesome offenses of the Muslims, and more alleged atrocities were expressed in inflammatory images derived from hagiography. Perhaps with the wisdom of hindsight, Robert has Urban advise that none but knights should go, not the old and feeble, nor priests without the permission of their bishops, "for such are more of a hindrance than aid, more of a burden than advantage ... nor ought women to set out at all, without their husbands or brothers or legal guardians". A later version by Baldric, archbishop of Dol, reported the sermon as focusing on the offenses of the Muslims and the reconquest of the Holy Land, and that Urban deplored the violence of the Christian knights of Gaul. He wanted the violence of knights to be ennobled in the service of Christ, defending the churches of the East as if defending a mother. Guibert, abbot of Nogent, also has Urban emphasize the reconquest of the Holy Land more than providing aid to the Greeks or other Christians there. This may, as in the case of Robert and Baldric, be due to the influence of the Gesta Francorum's account of the reconquest of Jerusalem.
A general call was sent out to the knights and nobles of France. Urban apparently knew in advance of the day that Raymond IV of Toulouse was prepared to take up arms. Urban himself spent a few months preaching the Crusade in France, while papal legates spread the word in the south of Italy, during which time the focus presumably turned from helping Alexios to taking Jerusalem. Urban's letter to the faithful "waiting in Flanders" laments that Turks, in addition to ravaging the "churches of God in the eastern regions," have seized "the Holy City of Christ, embellished by his passion and resurrection—and blasphemy to say it—have sold her and her churches into abominable slavery." Yet he does not explicitly call for the reconquest of Jerusulem. Rather he explicitly calls for the military "liberation" of the Eastern Churches and appoints Adhemar of Le Puy to lead the Crusade, to set out on the day of the Assumption of Mary, 15 August. Pope Urban's speech ranks as one of the most influential speeches ever, launching holy wars that occupied the minds and forces of western Europe for 200 years before their ultimate failure.
Role of women, children, and class
Women were intricately connected with the crusades, aiding the recruitment of crusading men, taking on responsibility in their absence, and providing financial and moral support. Historians argue that the most significant role played by women in the West was maintaining the status quo. Landholders left for the Holy Land, leaving control of their estates with regents, often wives or mothers. The Church recognized that risk to families and estates might discourage crusaders, so special papal protection formed part of the crusading privilege. A few women took up the cross themselves to go on the crusade. For example, Eleanor of Aquitaine joined her husband, Louis VII, and some non-aristocratic women were involved in tasks considered feminine like washerwoman. More controversial was women taking an active part, which threatened their femininity, with accounts of women fighting coming mostly from Muslim historians with the aim of portraying Christian women as barbaric and ungodly due to their acts of killing. Christian accounts portray women fighting only in rare situations for the preservation of their camps and lives.
Less historically certain was a Children's Crusade movement in France and Germany in 1212 that attracted large numbers of peasant teenagers and young people, with some under the age of 15. They were convinced that they could succeed where older and more sinful crusaders had failed: the miraculous power of their faith would triumph where the force of arms had not. Many parish priests and parents encouraged such religious fervor and urged them on. The pope and bishops opposed the attempt but failed to stop it entirely. A band of several thousand youth and young men, led by a German named Nicholas, set out for Italy. About a third survived the march over the Alps and got as far as Genoa; another group went to Marseilles. The luckier ones eventually managed to return home, but many others were sold as lifetime slaves on the auction blocks of Marseilles slave dealers.
Three crusading efforts among the peasants occurred in the middle 1250s and again in the early 1300s. The first, the Shepherds' Crusade of 1251, was preached in northern France. After meeting with Blanche of Castile, however, it became disorganized and had to be disbanded by the government. The second, in 1309, occurred in England, northeastern France, and Germany, and had as many as 30,000 peasants arriving at Avignon before being disbanded. The last one, in 1320, had similar origins as the first shepherds' crusade but quickly turned into a series of attacks on clergy and Jews, and was forcibly dispersed.
The first crusade established the first four Crusader states in the Eastern Mediterranean: the County of Edessa (1098 until 1149), the Principality of Antioch (1098 until 1268), Kingdom of Jerusalem (1099 until 1291) and the County of Tripoli (1104, although Tripoli itself was not conquered until 1109, to 1289). The Armenian Kingdom of Cilicia had its origins before the Crusades, but was granted the status of a kingdom by Pope Innocent III, and later became fully westernized by the (French) Lusignan dynasty. These states were recognised by Jonathan Riley-Smith as the first experiments in "Europe Overseas". The general name given to them is Outremer(French: outre-mer) for "overseas" and was often used as a synonym for the Levant of Renaissance.
Richard I of England conquered Cyprus during the third crusade who eventually sold it to the displaced King of Jerusalem Guy of Lusignan in 1192. Guy went on to found a dynasty that lasted until 1489 when control passed to the Republic of Venice. Cyprus became a prosperous Medieval Kingdom, a commercial and trading hub of Western Christendom in the Middle East.
After the fourth crusade the treaty called Partitio terrarum imperii Romaniae for "partition of the lands of the empire of Romània established the Latin Empire and arranged the partition of the Byzantine territory among the participants of the Crusade, with the Republic of Venice being the greatest beneficiary. In October October 1204 a 24-man committee consisting of 12 Venetians and 12 representatives of the other Crusader leaders agreed to give the Latin Emperor direct control of one fourth of the Byzantine territory, Venice three eighths , including three eighths of the city of Constantinople and divide the remaining three eighths among the other crusader leaders. Thus began the period of the history of Greece known as Frankokratia or Latinokratia ("Frankish/Latin rule"), where Catholic West European nobles, mostly from France and Italy, established states on former Byzantine territory and ruled over the mostly Orthodox native Byzantine Greeks. The Partitio Romànie is a valuable document for the administrative divisions (episkepseis) and estates of the various Byzantine magnate families ca. 1203, as well as the areas still controlled by the Byzantine central government at the time.
One factor in the eventual decline and fall was the disunity and conflict that was endemic between the various Latin Christian interests of the Eastern Mediterranean. Pope Martin IV hopelessly compromised the Papacy supporting Charles of Anjou; and the botched secular "Crusades" against Sicily and Aragon greatly tarnished its spiritual power. The collapse of its moral authority and the rise of nationalism rang the death knell for Crusading, and would ultimately lead to the Avignon Papacy and the Western Schism
In 1256 the Venetians were evicted from Tyre, prompting the War of Saint Sabas over territory in Acre claimed by both Genoa and Venice. Venice conquered the disputed property, destroying Saint Sabas' fortifications, but was unable to expel the Genoese. During a blockade of 14 months Genoa allied to Philip of Monfort, John of Arsuf and the Knights Hospitaller while Venice was supported by the Count of Jaffa and the Knights Templar. By 1261, the Genoese were expelled but Pope Urban IV, concerned of the impact of the war on the defences against the Mongols, organised a peace council. The conflict resumed in 1264 when the Genoese received aid from Michael VIII Palaiologos, Emperor of Nicaea and Venice failed in an attempt to conquer Tyre. Both sides employed Muslim soldiers, mostly Turcopoles, against their Christian foes and the Genoese had made an alliance with Baybars. The warfare between Genoa and Venice had a significant negative impact on the Kingdom's ability to withstand external threats to its existence. Except for the religious buildings, most of the fortified buildings in Acre had been destroyed at one point and it looked like it had been ravaged by a Muslim army. According to Rothelin, the continuator of William of Tyre's History, 20,000 men had lost their lives in the conflict at a time when the Crusader states were chronically short on soldiery. The war ended in 1270 and in 1288 Genoa finally received their quarter in Acre back.
In 1268 Saint Louis’s brother Charles executed Conradin — a great-grandson of Isabella I of Jerusalem, principal pretender to the throne of Jerusalem — when seizing Sicily from the Holy Roman Empire. Charles went on to purchase the rights to Jerusalem from Maria of Antioch — the only remaining grandchild of Queen Isabella— creating a rival claim to that of Hugh III of Cyprus, who was a great grandson of Queen Isabella. Charles spent his life striving to assemble a Mediterranean empire. He and Louis regarded themselves as God's instruments to uphold the Papacy.
In 1266 Charles had seized, with Sicily, parts of the eastern Adriatic it had previously controlled as well as Corfu, Butrinto, Avlona and Suboto. The Treaty of Viterbo was agreed with the exiled Baldwin II of Constantinople and William II Villehardouin with the heirs of both the Latin princes were to marry children of Charles, and Charles was to have the reversion of the Empire and principality should the couples have no heirs. He also turned his brother's Crusade to his own advantage persuading Louis to direct the Eighth Crusade against his rebel vassals in Tunis. Louis’s death, Illness among the Crusaders and a storm that devastated his fleet forced him to postpone his designs against Constantinople. Michael VIII Palaeologus was alarmed by Charles’s planned Crusade to restore the Latin Empire that had fallen in 1261 and Charles's expansion in the Mediterranean. Palaeologus delayed Charles by beginning negotiations with Pope Gregory X for a union between the Greek and the Latin churches. At the Council of Lyon, a Union of Churches was declared, and Charles and Philip of Courtenay were compelled to extend a truce with Byzantium. The union would later prove to be unacceptable to the Greeks. Palaeogus also provided Genoa and with funds to encourage the revolts in Charles’s northern Italian territories.
The accession of a French pope, Martin IV, in 1281 brought the full power of the Papacy into line behind Charles' plans. He campaigned unsuccessfully in Albania and Achaea before preparing to launch the body of his Crusade (400 ships carrying 27,000 mounted knights) against Constantinople. However, Palaeogus allied with Peter III of Aragon to encourage an uprising known as the Sicilian Vespers in which the Crusader fleet was abandoned and burnt. The Sicilians appealed to King Peter who was proclaimed king with the Angevin house exiled forever from Sicily. Pope Martin excommunicated Peter and called a Crusade against Aragon before, in 1287, Charles died allowing Henry II of Cyprus to reclaim the Kingdom of Jerusalem.
The mainland Crusading states of the middle eastern Outremer were extinguished with the fall of Tripoli in 1289, and Acre in 1291. The remaining Latin Christians largely left for various destinations in the Frankokratia, were killed or enslaved. Minor crusading efforts lingered into the 14th century. Peter I of Cyprus captured and sacked Alexandria in 1365 in what became known as the Alexandrian Crusade though his motivation for as much commercial as it was religious. Louis II, Duke of Bourbon led a French-Genoese campaign in 1390 against Muslim pirates in North Africa and based in Mahdia called the Mahdian Crusade. After a ten week siege, the crusaders lifted their siege with the signing of a ten-year truce.
Central to the debate on crusading ethics are the military orders, particularly the Hospitallers and the Templars. To a modern sensibility it is strange that the church could reconcile monasticism with soldiering. Both the Hospitallers and the Templars became international organisations with depots located across the countries of Western Europe as well as in the East. In contrast the Teutonic knights successfully moved their attentions to the Baltic and the Spanish military orders of Santiago, Calatrava and Alcantara concentrated on the Iberian Peninsula. The Knights of the Order of the Hospital of St John of Jerusalem were founded in 1099 in the aftermath of the first crusade. The order included military, medical and pastoral brothers. Following the fall of Acre they escaped to Cyprus and successively conquered and ruled both Rhodes (1309-1522) and Malta (1530-1801). The Poor Knights of Christ and the Temple of Solomon were founded in 1118 to protect pilgrims en route to Jerusalem. However, they quickly became immensely rich and powerful through banking and real estate with property throughout Christendom. In 1322 the King of France suppressed the order on spurious charges of sodomy, magic and heresy but more probably for financial and political reasons.
Politics and culture
Crusades continued to take place against the Christian Greeks who had been expelled from Constantinople in the Fourth Crusade. With their recapture of the city in 1261, crusades were called by the papacy from 1262 through 1281 to drive the Greeks back out of Constantinople, with little result. The Crusades influenced the attitude of the western Church and people towards warfare. The frequent calling of crusades habituated the clergy to the use of violence. The crusades also sparked debate about the legitimacy of taking lands and possessions from pagans on purely religious grounds that would arise again in the 15th and 16th centuries with the Age of Discovery. The needs of crusading warfare also stimulated secular governmental developments, although this was not always a totally positive development. The resources collected for crusading could have been used by the developing states for local and regional needs instead of in far away lands. The crusades impacted the papacy in a number of ways. Although they did raise the prestige of the papacy, the sheer effort required to support the crusaders took away resources that might have been better employed elsewhere. The crusades did increase the control of the papal curia over the entire western Church, by extending the system of papal taxation throughout the whole ecclesiastical structure of the west. The crusades also stimulated the development of the indulgence system that grew greatly in extent in late medieval Europe, later to spark the Protestant Reformation in the early 1500s.
The military experiences of the crusades had a limited degree of influence on European castle design; for example, Caernarfon Castle, in Wales, begun in 1283, directly reflects the style of fortresses Edward I had observed while fighting in the Crusades. The crusades otherwise seem to have had little effect on military tactics or organization, mainly because it was difficult to transfer the lessons that were learned in the Holy Land to the different terrain and fighting styles of Europe. The First Crusade ignited a long tradition of organized violence against Jews in European culture. The Albigensian Crusade was initiated by the Catholic Church to eliminate the Cathar heresy in Languedoc. The violence led to France's acquisition of lands with closer cultural and linguistic ties to Catalonia. The Albigensian Crusade also had a role in the creation and institutionalization of both the Dominican Order and the Medieval Inquisition.
The Crusades were criticised by some contemporaries such as Roger Bacon who felt the Crusades were not effective because, "those who survive, together with their children, are more and more embittered against the Christian faith." Nevertheless the movement was widely supported in Europe long after the fall of Acre in 1291.
The Orthodox Christian Byzantine Greeks were scandalised by the formation of military religious orders and also objected when the Crusaders did not, as promised, restore territory previously held by Byzantium.
The need to raise, transport and supply large armies led to a flourishing of trade throughout Europe between Europe and the Outremer. Genoa and Venice flourished through profitable trading colonies in the crusader states, both in the Holy Land and later in captured Byzantine territory.
Age of Crusade
Although the reconquest of the Iberian Peninsula from Muslims began in the 8th century and reached its turning point around 100 years before the preaching of the First Crusade in 1095, with the recapture of Toledo in 1085, Urban II also tied the ongoing wars in Iberia to his preaching of the First Crusade and the crusading effort. It was through a papal encyclical of 1123 by Pope Calixtus II that these wars attained the status of crusades. After this, the papacy declared Iberian crusades in 1147, 1193, 1197, 1210, 1212, 1221 and 1229. Crusading privileges were also given to those people who were helping the military orders – both the traditional Templars and Hospitallers as well as the specifically Iberian orders that were founded and eventually merged into two main orders – that of the Order of Calatrava and the Order of Santiago. From 1212 to 1265, the Christian kingdoms of Iberia drove Muslim rule into the far south of the Iberian Peninsula, confined to the small Emirate of Granada. In 1492, this remnant was conquered and Muslims and Jews were expelled from the peninsula.
People's Crusade (1096)
Urban inspired the preaching of Peter the Hermit who eventually led perhaps as many as 20,000 people, mostly peasants, towards the Holy Land just after Easter 1096. When they reached the Byzantine Empire, Alexios urged them to wait for the western nobles, but the "army" insisted on proceeding and was ambushed outside Nicaea by the Turks, with only about 3000 people escaping the ambush. This crusade is considered a part of the First Crusade.
First Crusade (1095–1099) and immediate aftermath
The official crusader armies set off from France and Italy at different times in August and September 1096, with Hugh of Vermandois departing first, and the bulk of the army dividing into four parts travelling separately to Constantinople. In all, the western forces may have totaled as many as 100,000 persons, counting both combatants and non-combatants. The armies journeyed eastward by land toward Constantinople, where they received a wary welcome from the Byzantine Emperor. Pledging to restore lost territories to the empire, the main army, mostly French and Norman knights under baronial leadership, marched south through Anatolia. The leaders of the First Crusade included Godfrey of Bouillon, Robert Curthose, Hugh of Vermandois, Baldwin of Bouillon, Tancred de Hauteville, Raymond of Toulouse, Bohemond of Taranto, and Robert II, Count of Flanders, and Stephen, Count of Blois. The King of France and Henry IV, Holy Roman Emperor, were both in conflict with the Papacy and did not take part. When the French crusaders crossed into Germany in spring 1096, units of Crusaders massacred hundreds or thousands of Jews in the cities of Speyer, Worms, Mainz and Cologne, despite the efforts by Catholic bishops to protect the Jews. Major leaders included Emicho and Peter the Hermit. Chazan says "the range of anti-Jewish activity was broad, extending from limited, spontaneous violence to full-scale military attacks on the Jewish communities of Mainz and Cologne." This was the first major outbreak of anti-Jewish violence in Christian Europe and was cited by Zionists in the 19th century as indicating the need for a state of Israel.
The Crusader armies initially fought the Turks at the lengthy Siege of Antioch that began in October 1097 and lasted until June 1098. Once inside the city the Crusaders massacred the Muslim inhabitants and pillaged the city. However, a large Muslim relief army under Kerbogha immediately besieged the victorious Crusaders within Antioch. Bohemond of Taranto led a successful rally of the crusader army and defeated Kerbogha's army on 28 June. Bohemond and his men retained control of Antioch, in spite of his pledge to the Byzantine emperor. Most of the surviving crusader army marched south, moving from town to town along the coast, finally reaching the walls of Jerusalem on 7 June 1099 with only a fraction of their original forces.
Jews and Muslims fought together to defend Jerusalem against the invading Franks. On 15 July 1099 the crusaders entered the city. They proceeded to massacre the remaining Jewish and Muslim civilians and pillaged or destroyed mosques and the city itself. As a result of the First Crusade, four main Crusader states were created: the County of Edessa, the Principality of Antioch, the County of Tripoli, and the Kingdom of Jerusalem.
On a popular level, the preaching of the First Crusade unleashed a wave of impassioned, personally felt pious Christian fury that was expressed in the massacres of Jews that accompanied and preceded the movement of the crusaders through Europe, as well as the violent treatment of the "schismatic" Orthodox Christians of the east.
Following this crusade was a second, less successful wave of crusaders, known as the Crusade of 1101, in which Turks led by Kilij Arslan defeated the crusaders in three separate battles in a response to the First Crusade. Sigurd I of Norway was the first European king to visit the crusading states, as well as the first European king to take part in a crusading campaign, although his expedition was as much pilgrimage as crusade. His fleet helped at the Siege of Sidon. Also in 1107, Bohemond I of Antioch attacked the Byzantines at Avlona and Dyrrachium, in what is occasionally called Bohemond's Crusade, which ended in September 1108 with a defeat for Bohemond and his retiring to Italy.
Further efforts in the 1120s included a crusade preached by Pope Calixtus II around 1120, which became the Venetian Crusade of 1122–1124; a pilgrimage of Count Fulk V of Anjou in 1120; an effort by Conrad III of Germany in 1124, of which few details are known; and the Damascus Crusade of 1129 by Fulk V, which resulted in the recognition of the Knights Templar by Pope Honorius II in January 1129. Some historians have seen Pope Innocent II's grant in 1135 of the same crusading indulgences to those who opposed papal enemies as the first of the politically motivated crusades against papal opponents, but other historians do not agree.
The Crusader states were initially secure, but Imad ad-Din Zengi, who was appointed governor of Mosul in 1127, captured Aleppo in 1128 and Edessa in 1144. These defeats led Pope Eugenius III to call for another crusade on 1 March 1145.
Second Crusade (1147–1149)
The new crusade was called for by various preachers, most notably by Bernard of Clairvaux. French and South German armies, under the Kings Louis VII and Conrad III respectively, marched to Jerusalem in 1147 but failed to win any major victories, launching a failed pre-emptive siege of Damascus. On the other side of the Mediterranean, however, the Second Crusade met with great success as a group of Northern European Crusaders stopped in Portugal, allied with the Portuguese King, Afonso I of Portugal, and retook Lisbon from the Muslims in 1147. A detachment from this group of crusaders helped Count Raymond Berenguer IV of Barcelona conquer the city of Tortosa the following year.[page needed] In the Holy Land by 1150, both the kings of France and Germany had returned to their countries without any result. Bernard of Clairvaux, who in his preachings had encouraged the Second Crusade, was upset with the amount of misdirected violence and slaughter of the Jewish population of the Rhineland. A followup to this crusade was the pilgrimage of Henry the Lion, Duke of Saxony, in 1172 that is sometimes labeled a crusade.
Contemporaneous with the Second Crusade, Saxons and Danes fought against Polabian Slavs in the Wendish Crusade or First Northern Crusade. The Wends defeated the Danes and the Saxons did not contribute much to the crusade. The Wends did acknowledge the overlordship of the Saxon ruler, Henry the Lion. Further crusading actions continued although no papal bulls were issued calling new crusades. Efforts to conquer the Wends began again in 1160 under Henry the Lion, continuing until 1162, when the Wends were defeated at the Battle of Demmin.
Third Crusade (1187–1192)
The Muslims had long fought among themselves, but they were finally united by Saladin, who created a single powerful state. Following his victory at the Battle of Hattin he easily overwhelmed the disunited crusaders in 1187 and retook Jerusalem on 29 September 1187. Terms were arranged and the city surrendered, with Saladin entering the city on 2 October 1187.
Saladin's victories shocked Europe. On hearing news of the Siege of Jerusalem (1187), Pope Urban III died of a heart attack on 19 October 1187. On 29 October Pope Gregory VIII issued a papal bull Audita tremendi, proposing the Third Crusade. To reverse this disaster Emperor Frederick I Barbarossa (r. 1152–1190) of Germany, King Philip II of France, (r. 1180–1223), and King Richard I (r. 1189–1199) of England all organized forces for the crusade. Frederick died en route and few of his men reached the Holy Land. The other two armies arrived but were beset by political quarrels. Philip returned to France, but left most of his forces behind. Richard captured the island of Cyprus from the Byzantines in 1191. After a long siege, Richard recaptured the city of Acre. The Crusader army headed south along the Mediterranean coast. They defeated the Muslims near Arsuf, recaptured the port city of Jaffa, and were in sight of Jerusalem, but supply problems prevented them from taking the city and the crusade ended without the taking of Jerusalem. Richard left the following year after negotiating a treaty with Saladin. The treaty allowed trade for merchants and unarmed Christian pilgrims to make pilgrimages to Jerusalem, while it remained under Muslim control.
Northern crusades (1193–1290)
Pope Celestine III called for a crusade against pagans in Northern Europe in 1193. Bishop Berthold of Hanover arrived with a large contingent of crusaders in 1198 but was killed in battle and his forces were defeated. To avenge Berthold's defeat, Pope Innocent III issued a bull declaring a crusade against the Livonians. Albrecht von Buxthoeven, consecrated as bishop in 1199, arrived the following year with a large force, and established Riga as the seat of his bishopric in 1201. In 1202 he formed the Livonian Brothers of the Sword to aid in the conversion of the pagans to Christianity and, more importantly, to protect German trade and secure German control over commerce.
The Livonian Crusade was proclaimed by Pope Innocent III against the Livonians who were mostly still pagan. The Livonians were conquered and converted between 1202 and 1209. A crusade against the Prussians was called by Pope Honorius III in 1217. Konrad of Masovia gave Chelmno to the Teutonic Knights in 1226 to serve the knights as a base for crusades against the Prussians, In 1236 the Livonian Sword Brothers were defeated by the Lithuanians at Saule, and in 1237 Pope Gregory IX merged the remaining Sword Brothers into the Teutonic Knights. In 1240 the Battle of the Neva was fought, where the Swedes, attempting to extend the northern crusades to the Russians, were defeated. By 1249, the Teutonic Knights had completed their conquest of the Prussians, which they ruled as a fief of the German emperor. The Knights then moved on to conquer and convert the pagan Lithuanians, a process that lasted into the 1380s. The Teutonic Order's attempts to conquer Orthodox Russia (particularly the Republics of Pskov and Novgorod), an enterprise endorsed by Pope Gregory IX, can also be considered as a part of the Northern Crusades. One of the major blows for the idea of the conquest of Russia was the Battle of the Ice in 1242.
German Crusade (1195–1198)
Emperor Henry VI took the cross in 1195. Henry's health did not allow him to lead the forces in person, and leadership devolved on Conrad of Wittelsbach, the Archbishop of Mainz. The forces landed at Acre in September 1197 and captured some towns, including Sidon and Beirut, but Henry's death in late 1197 meant that most of the crusaders returned to Germany in the middle of 1198.
Fourth Crusade (1202–1204)
The Fourth Crusade never reached the Holy Land. Instead, it became a vehicle for the political ambitions of Doge Enrico Dandolo and the German King Philip of Swabia who was married to Irene of Byzantium. Dandelo saw an opportunity to expand Venice's possessions in the near east while Philip saw the crusade as a chance to restore his exiled nephew, Alexios IV Angelos to the throne on Byzantium. Pope Innocent III initiated recruitment for the crusade in 1200 with preaching taking place in France, England, and Germany, although the bulk of the efforts were in France. The Crusaders lacked the funds to pay for the fleet and provisions from the Venetians so agreed in payment to share what could be looted and restore Alexius. As collateral for this the crusade seized the Christian city of Zara on 24 November 1202. Innocent was appalled and excommunicated the crusaders. The crusaders met with limited resistance in their initial siege of Constantinople, sailing down the Dardanelles and breaching the sea walls. However, Alexius was strangled after a palace coup robbing them of their success and they had to repeat the siege in April 1204. This time the city was ransacked, churches pillaged and large numbers of the citizens butchered. The crusaders took their rewards; dividing the Empire into Latin fiefs and Venetian colonies. In April 1205, the crusaders were largely annihilated by Bulgars and remaining Greeks at Adrianople, where Kaloyan of Bulgaria captured and imprisoned the new Latin emperor Baldwin of Flanders. While deploring the means, the papacy initially supported this apparent forced reunion between the Eastern and Western churches. The Fourth Crusade effectively left two Roman Empires in the East, one Latin "Empire of the Straits" until 1261 and a Byzantine rump ruled from Nicea which later regained control in the absence of the Venetian fleet. Venice was the sole beneficiary in the long run.
In the Enlightenment, historians criticized the misdirection of the crusading movement. In particular they pointed to the Fourth Crusade which instead of attacking Islam attacked another Christian power – the (Eastern) Roman Empire. David Nicolle says the Fourth Crusade has always been controversial in terms of the "betrayal" of Byzantium.
Eight hundred years after the Fourth Crusade, Pope John Paul II twice expressed sorrow for the events of the Fourth Crusade. In 2001, he wrote to Christodoulos, Archbishop of Athens, saying, "It is tragic that the assailants, who set out to secure free access for Christians to the Holy Land, turned against their brothers in the faith. The fact that they were Latin Christians fills Catholics with deep regret." In 2004, while Bartholomew I, Patriarch of Constantinople, was visiting the Vatican, John Paul II asked, "How can we not share, at a distance of eight centuries, the pain and disgust." This has been regarded as an apology to the Greek Orthodox Church for the terrible slaughter perpetrated by the warriors of the Fourth Crusade.
In April 2004, in a speech on the 800th anniversary of the city's capture, Ecumenical Patriarch Bartholomew I formally accepted the apology. "The spirit of reconciliation is stronger than hatred," he said during a liturgy attended by Roman Catholic Archbishop Philippe Barbarin of Lyon, France. "We receive with gratitude and respect your cordial gesture for the tragic events of the Fourth Crusade. It is a fact that a crime was committed here in the city 800 years ago." Bartholomew said his acceptance came in the spirit of Pascha. "The spirit of reconciliation of the resurrection... incites us toward reconciliation of our churches."
Albigensian Crusade (1208–1241)
The Albigensian Crusade was launched in 1208 in order to eliminate the heretical Cathars of Occitania (modern-day southern France). It was a decades-long struggle that had as much to do with northern France's desire to extend its control southwards as it did with Northern France's desire to eliminate heresy. In the end, the Cathars were driven underground and the independence of southern France was eliminated. Pope Honorius III called a crusade against supposed Cathar heretics in Bosnia. There were rumors that there was an anti-pope of the Cathars named Nicetas, although whether such a figure ever existed is unclear. Hungarian forces responded to the papal calls in two efforts in 1234 and 1241, with the second one ending because of the Mongol invasion of Hungary in 1241. The Bosnian church was Catholic in theology, but continued to be in schism with the Roman Catholic Church well past the end of the Middle Ages.
Fifth Crusade (1217–1221)
Pope Innocent III declared a new crusade to commence in 1217, along with his summoning of the Fourth Council of the Lateran in 1215. The majority of the crusaders came from Germany, Flanders, and Frisia, along with a large army from Hungary led by King Andrew II and other forces led by Duke Leopold VI. The forces of Andrew and Leopold arrived in Acre in October 1217 but little was accomplished and Andrew returned to Hungary in January 1218. After the arrival of more crusaders, Leopold and the king of Jerusalem, John of Brienne, laid siege to Damietta in Egypt, which they captured finally in November 1219. Further efforts by the papal legate, Pelagius, to invade further into Egypt led to no gains. Blocked by forces of the Ayyubid Sultan Al-Kamil, the crusaders were forced to surrender. Al-Kamil forced the return of Damietta and agreed to an eight-year truce and the crusaders left Egypt.
Sixth Crusade (1228–1229)
Emperor Frederick II had repeatedly vowed a crusade but failed to live up to his words, for which he was excommunicated by Gregory IX in 1228. He nonetheless set sail from Brindisi in June 1228 and landed at Saint-Jean d'Acre in September 1228, after a stopover in Cyprus. There were no battles as Frederick made a peace treaty with Al-Kamil, the ruler of Egypt. This treaty allowed Christians to rule over most of Jerusalem and a strip of territory from Acre to Jerusalem, while the Muslims were given control of their sacred areas in Jerusalem. In return, Frederick pledged to protect Al-Kamil against all his enemies, even if they were Christian.
A followup to this crusade was the effort by King Theobald I of Navarre in 1239 and 1240 that had originally been called in 1234 by Pope Gregory IX to assemble in July 1239 at the end of a truce. Besides Theobald, Peter of Dreux and Hugh, Duke of Burgundy and other French nobles took part. They arrived in Acre in September 1239 and after a defeat in November, Theobald arranged a treaty with the Muslims that returned territory to the crusading states, but caused much disaffection within the crusaders. Theobald returned to Europe in September 1240. Also in 1240, Richard of Cornwall, younger brother of King Henry III of England, took the cross and arrived in Acre in October. He then secured the ratification of Theobald's treaty and left the Holy Land in May 1241 for Europe.
Seventh Crusade (1248–1254)
In the summer of 1244 a Khwarezmian force summoned by the son of al-Kamil, al-Salih Ayyub, stormed Jerusalem and took it. The Franks allied with Ayyub's uncle Ismail and the emir of Homs and the combined forces were drawn into battle at La Forbie in Gaza. The crusader army and its allies were completely defeated within forty-eight hours by the Khwarezmian tribesmen. In showing utter agony, a Templar knight lamented :
|“||Rage and sorrow are seated in my heart...so firmly that I scarce dare to stay alive. It seems that God wishes to support the Turks to our loss...ah, lord God...alas, the realm of the East has lost so much that it will never be able to rise up again. They will make a Mosque of Holy Mary's convent, and since the theft pleases her Son, who should weep at this, we are forced to comply as well...Anyone who wishes to fight the Turks is mad, for Jesus Christ does not fight them any more. They have conquered, they will conquer. For every day they drive us down, knowing that God, who was awake, sleeps now, and Muhammad waxes powerful.||”|
King Louis IX of France organized a crusade after taking the cross in December 1244, with preaching and recruitment taking up the time between 1245 and 1248. Louis' forces set sail from France in May 1249 and landed near Damietta in Egypt on 5 June 1249. Waiting until the end of the Nile flood, the army marched into the interior in November and by February were near El Manusra. But they were defeated near there and King Louis was captured on the retreat towards Damietta that resulted. Louis was ransomed for 800,000 bezants and a ten-year truce was agreed. Louis then went to Syria where he remained until 1254, working to solidify the kingdom of Jerusalem and constructing fortifications.
Eighth and Ninth Crusade (1270–1272)
Ignoring his advisers, in 1270 Louis IX again attacked the Arabs in Tunis in North Africa. He picked the hottest season of the year for campaigning and his army was devastated by disease. The king himself died, ending the last major attempt to take the Holy Land. The Mamluks, led by Baibars, eventually drove the Franks from the Holy Land. During 1265 through 1271, he had driven the Franks to a few small coastal outposts. His armies slaughtered or enslaved every Christian in the city of Antioch. The future Edward I of England undertook to crusade with Louis IX, but was delayed and did not arrive in North Africa until November 1270. After the death of Louis, Edward went to Sicily, but then went on to Acre in May 1271. His forces were too small to make much difference, and he was upset at the conclusion of a truce between the king of Jerusalem, Hugh, and Baibars. Although Edward learned of his father's death and his succession to the throne in December 1272, he did not return to England until 1274, although he accomplished little in the Holy Land.
Aragonese Crusade (1284-1285)
The Crusade of Aragón, was declared by Pope Martin IV against King Peter III of Aragon, in 1284 and 1285. Peter was supporting the anti-Angevin forces in Sicily following the Sicilian Vespers, and the papacy supported Charles of Anjou. Pope Boniface VIII proclaimed a crusade against Frederick, the younger brother of Peter, in 1298, but was unable to prevent Frederick's crowning and recognition as King of Sicily.
Crusades of the 15th century
Several crusades were launched in the 15th century to counter the expanding Ottoman Empire starting in 1396 with Sigismund of Luxemburg, king of Hungary. Many French nobles joined Sigismund's forces, including John the Fearless, son of the Duke of Burgundy, who was appointed military leader of the crusade. Although Sigismund advised the crusaders to adopt a defensive posture once they reached the Danube, the crusaders instead besieged the city of Nicopolis. The Ottomans met the crusaders in the Battle of Nicopolis on 25 September 1396, defeating the Christian forces and capturing 3,000 prisoners.
The Hussite Crusade(s), also known as the "Hussite Wars," or the "Bohemian Wars," involved the military actions against the followers of Jan Hus in Bohemia in the period 1420 to around 1431. Crusades were declared five times in that period – in 1420, 1421, 1422, 1427 and in 1431. The net effect of these expeditions was to force the Hussite forces, which disagreed on many doctrinal points, to unite to drive out the invaders. The wars were brought to a conclusion in 1436 with the ratification of the Compactata of Iglau by the Church. In April 1487, Pope Innocent VIII called a crusade against the Waldensian heretics of Savoy, the Piedmont, and the Dauphiné in southern France and northern Italy. The only efforts actually undertaken were against heretics in the Dauphiné, and resulted in little change.
The Polish-Hungarian king, Władysław Warneńczyk invaded the recently conquered Ottoman territory and reached Belgrade in January 1444. Negotiations over a truce eventually led to an agreement, that was repudiated by Sultan Murad II within days of its ratification. Further efforts by the crusaders ended in the Battle of Varna on 10 November 1444 which, although resulting in a draw between the two forces, led to the crusaders withdrawing. This withdrawal led to the fall of Constantinople in 1453, as it was the last Western attempt to help the Byzantine Empire.
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- In the Footsteps of St. Paul: Papal Visit to Greece, Syria & Malta – Words. EWTN.
- "Pope sorrow over Constantinople". BBC News. June 29, 2004.
- Phillips. The Fourth Crusade, p. xiii.
- In Communion » News – issue 33
- Lock Routledge Companion pp. 163–165
- Lock Routledge Companion pp. 172–173
- Lock Routledge Companion pp. 168–169
- Riley-Smith Crusades pp. 179–180
- Hindley Crusades pp. 561–562
- Lock Routledge Companion p. 169
- Ashbridge Crusades pp. 566–568
- Ashbridge Crusades p. 569
- Ashbridge Crusades pp. 574–576
- Tyerman God's War pp. 770–775
- Hindley Crusades pp. 194–195
- Lock Routledge Companion p. 178
- Strayer "Crusades of Louis IX" Later Crusades p. 487
- Tyerman God's War pp. 816–817
- Michaud, The History of the Crusades, Vol. 3, p. 18 ; available in full at Google Books. Note that in a footnote Michaud claims reliance on "the chronicle of Ibn Ferat" (Michaud, Vol.3, p.22) for much of the information he has concerning the Mussulmans.
- Lock Routledge Companion p. 164
- Lock Routledge Companion p. 186
- Lock Routledge Companion p. 200
- Lock Routledge Companion pp. 201–202
- Lock Routledge Companion p. 204
- Lock Routledge Companion pp. 202–203
- Asbridge, Thomas (2011). The Crusades: The Authoritative History of the War for the Holy Land. Ecco. ISBN 978-0-06-078729-5.
- Asbridge, Thomas (2005). The First Crusade: A New History: The Roots of Conflict between Christianity and Islam. Oxford University Press. ISBN 978-0-19-518905-6.
- Barber, Malcolm (1992). The Two Cities: Medieval Europe 1050–1320. London: Routledge. ISBN 0-415-09682-0.
- Bernard of Clairvaux (2000). In Praise of the New Knighthood. Cistercian Publications. ISBN 978-0879071202.
- Brand, Charles M. (April 1962). "The Byzantines and Saladin, 1185–1192: Opponents of the Third Crusade". Speculum 37 (2): 167–181. doi:10.2307/2849946. JSTOR 2849946.
- Bréhier, Louis (1908). "Crusades". Catholic Encyclopedia 4.
- Bull, Marcus (1999). "Origins". In Riley-Smith, Jonathan. The Oxford History of the Crusades. New York: Oxford University Press. pp. 15–34. ISBN 0-19-280312-3.
- Cohn, Norman (1970). The pursuit of the Millennium.
- Daniel, Norman (1979). The Arabs and Mediaeval Europe. Longman Group Limited. ISBN 0-582-78088-8.
- Davies, Norman (1997). Europe – A History. Pimlico. ISBN 0-7126-6633-8.
- Dickson, Gary (2008). The Children's Crusade: Medieval History, Modern Mythistory. Palgrave Macmillan.
- Edington, Susan B. and Lambert, Sarah (2002). Gendering the Crusades. New York: Columbia University Press.
- Esposito, John L. What Everyone Needs to Know about Islam.
- Findley, Carter Vaughan (2005). The Turks in World History. New York: Oxford University Press. ISBN 0-19-516770-8.
- Heng, Geraldine (2004). Empire of Magic: Medieval Romance and the Politics of Cultural Fantasy. Columbia University Press. ISBN 0-231-12527-7 Check
- Hillenbrand, Carole (1999). The Crusades: Islamic Perspectives. Edinburgh: Edinburgh University Press.
- Hindley, Geoffrey. The Crusades: Islam and Christianity in the Struggle for World Supremacy. New York: Carrol & Graf. ISBN 0-7867-1344-5.
- Hodgson, Natasha (2007). Women, Crusading and the Holy Land in Historical Narrative. Boydell.
- Holt, P. M. (1983). "Saladin and His Admirers: A Biographical Reassessment". Bulletin of the School of Oriental and African Studies, University of London 46 (2): 235–239. doi:10.1017/S0041977X00078824. JSTOR 615389.
- Housley, Norman (2006). Contesting the Crusades. Malden, MA: Blackwell Publishing. ISBN 1-4051-1189-5.
- Jackson, Peter (2007). The Seventh Crusade, 1244–1254.
- Kahf, Mohja (1999). Western Representations of the Muslim Women: From Termagant to Odalisque. University of Texas Press. ISBN 978-0-292-74337-3.
- Kolbaba, T. M. (2000). The Byzantine Lists: Errors of the Latins. University of Illinois.
- Lewis, Richard D. (2005). Finland: Cultural Lone Wolf. Intercultural Press. ISBN 978-1-931930-49-9.
- Lock, Peter (2006). Routledge Companion to the Crusades. New York: Routledge. ISBN 0-415-39312-4.
- Madden, Thomas F. (2005). The New Concise History of the Crusades. Lanham, MD: Rowman & Littlefield. ISBN 978-0-7425-3822-1.
- Marshall, Christopher (1994). Warfare in the Latin East, 1192-1291. Cambridge: Cambridge University Press. ISBN 9780521477420.
- Mayer, Hans Eberhard (1988). The Crusades (Second ed.). Oxford: Oxford University Press. ISBN 0-19-873097-7.
- Munro, Dana Carleton (January 1906). "The Speech of Pope Urban II at Clermont, 1095". American Historical Review 11 (2): 231–242. doi:10.2307/1834642. JSTOR 1834642.
- Nelson, Laura N. The Byzantine Perspective of the First Crusade.
- Nicholson, Helen (1997). "Women on the Third Crusade". Journal of Medieval History 23 (4): 335. doi:10.1016/S0304-4181(97)00013-4.
- Nicolle, David (2007). Crusader Warfare Volume II: Muslims, Mongols and the Struggle against the Crusades.
- Nicolle, David (2003). The First Crusade 1066–99: Conquest of the Holy Land. Campaign. Wellingborough, UK: Osprey. ISBN 1-84176-515-5.
- Nicolle, David (2011). The Fourth Crusade 1202–04: The Betrayal of Byzantium. Osprey Publishing.
- Pringle, Denys (1999). "Architecture in Latin East". In Riley-Smith, Jonathan. The Oxford History of the Crusades. New York: Oxford University Press. pp. 155–175. ISBN 0-19-280312-3.
- Owen, Roy Douglas Davis (1993). Eleanor of Aquitaine: Queen and Legend. Oxford, UK: Blackwell Publishing.
- Retso, Jan (2003). The Arabs in Antiquity: Their History from the Assyrians to the Umayyads. Routledge. ISBN 978-0-7007-1679-1.
- Riley-Smith, Jonathan (1973). The Feudal Nobility and the Kingdom of Jerusalem, 1174-1277. Hamden: Archon Books. ISBN 9780208013484.
- Riley-Smith, Jonathan (1990). The Atlas of the Crusades. New York: Facts on File. ISBN 0-8160-2186-4.
- Riley-Smith, Jonathan (2005). The Crusades: A Short History (Second ed.). New Haven, CT: Yale University Press. ISBN 0-300-10128-7.
- Riley-Smith, Jonathan (1997). The First Crusaders 1096–1131. New York, NY: Cambridge University Press.
- Rose, Karen (2009) "The Order of the Knights Templar"
- Runciman, Steven (1951). A History of the Crusades: The Kingdom of Acre and the Later Crusades (reprinted 1987 ed.). Cambridge University Press.
- Sinclair, Andrew (1995). Jerusalem: The Endless Crusade. New York: Crown Publishers.
- Strayer, Joseph Reese (1992). The Albigensian Crusades. University of Michigan Press. ISBN 0-472-06476-2.
- Strayer, Joseph R. (1969). "The Crusades of Louis IX". In Wolff, R. L. and Hazard, H. W. The Later Crusades, 1189–1311. pp. 487–521.
- Tolan, John Victor Norman (2002). Saracens: Islam in the Medieval European Imagination. Columbia University Press. ISBN 978-0-231-12333-4.
- Tolan, John; Veinstein, Gilles and Henry Laurens (2013). Europe and the Islamic World: A History. Princeton University Press. ISBN 978-0-691-14705-5.
- Tyerman, Christopher (1988). England and the Crusades, 1095–1588. Chicago, IL: University of Chicago Press. ISBN 0-226-82013-0.
- Tyerman, Christopher (2006). God's War: A New History of the Crusades. Cambridge, MA: Belknap Press. ISBN 978-0-674-02387-1.
- Vasilʹev, Aleksandr Aleksandrovich (1952). History of the Byzantine Empire: 324–1453. University of Wisconsin Press.
- Villegas-Aristizábal, L. (2009). "Anglo-Norman involvement in the conquest of Tortosa and Settlement of Tortosa, 1148–1180". Crusades (8): 63–129.
- Wickham, Chris (2009). The Inheritance of Rome: Illuminating the Dark Ages 400–1000. New York: Penguin Books. ISBN 978-0-14-311742-1.
- Zacour, Norman P. (1969). "The Children's Crusade". In Wolff, R. L. and Hazard, H. W. The Later Crusades, 1189–1311. pp. 325–342.
- Andrea, Alfred J. Encyclopedia of the Crusades. (2003)
- Asbridge, Thomas. The First Crusade: A New History: The Roots of Conflict between Christianity and Islam (2005)
- France, John. Western Warfare in the Age of the Crusades, 1000–1300 (1999)
- Hillenbrand, Carole. The Crusades, Islamic Perspectives. (2000)
- Holt, P.M. The Age of the Crusades: The Near East from the Eleventh Century to 1517. (1986)
- Phillips, Jonathan. Holy Warriors: A Modern History of the Crusades (2010)
- Riley-Smith, Jonathan, ed. The Atlas of the Crusades (1991)
- Riley-Smith, Jonathan. The Crusades, Christianity, and Islam (2011)
- Specialized studies
- Boas, Adrian J. Jerusalem in the Time of the Crusades: Society, Landscape, and Art in the Holy City under Frankish Rule (2001)
- Bull, Marcus, and Norman Housley, eds. The Experience of Crusading Volume 1, Western Approaches. (2003)
- Edbury, Peter, and Jonathan Phillips, eds. The Experience of Crusading Volume 2, Defining the Crusader Kingdom. (2003)
- Florean, Dana. "East Meets West: Cultural Confrontation and Exchange after the First Crusade." Language & Intercultural Communication, 2007, Vol. 7 Issue 2, pp. 144–151
- Folda, Jaroslav. Crusader Art in the Holy Land, From the Third Crusade to the Fall of Acre (2005)
- France, John. Victory in the East: A Military History of the First Crusade (1996)
- Harris, Jonathan. Byzantium and the Crusades. (2003)
- Hillenbrand, Car. The Crusades: Islamic Perspectives (1999)
- Housley, Norman. The Later Crusades, 1274–1580: From Lyons to Alcazar (1992)
- James, Douglas. "Christians and the First Crusade." History Review (Dec 2005), Issue 53
- Kagay, Donald J., and L. J. Andrew Villalon, eds. Crusaders, Condottieri, and Cannon: Medieval Warfare in Societies around the Mediterranean. (2003)
- Maalouf, Amin. Crusades Through Arab Eyes (1989)
- Madden, Thomas F. et al., eds. Crusades Medieval Worlds in Conflict (2010)
- Peters, Edward. Christian Society and the Crusades, 1198–1229 (1971)
- Powell, James M. Anatomy of a Crusade, 1213–1221, (1986)
- Queller, Donald E., and Thomas F. Madden. The Fourth Crusade: The Conquest of Constantinople (2nd ed. 1999)
- Riley-Smith, Jonathan.The First Crusade and the Idea of Crusading. (1986)
- Runciman, Steven. A History of the Crusades: Volume 2, The Kingdom of Jerusalem and the Frankish East (1952) vol 2 online free; A History of the Crusades: Volume 3, The Kingdom of Acre and the Later Crusades (1954); the classic 20th century history
- Setton, Kenneth ed., A History of the Crusades. (1969–1989), the standard scholarly history in six volumes, published by the University of Wisconsin Press
- Includes: The first hundred years (2nd ed. 1969); The later Crusades, 1189–1311 (1969); The fourteenth and fifteenth centuries (1975); The art and architecture of the crusader states (1977); The impact of the Crusades on the Near East (1985); The impact of the Crusades on Europe (1989)
- Smail, R. C. "Crusaders' Castles of the Twelfth Century" Cambridge Historical Journal Vol. 10, No. 2. (1951), pp. 133–149.
- Stark, Rodney. God's Battalions: The Case for the Crusades (2010)
- Tyerman, Christopher. England and the Crusades, 1095–1588. (1988)
- Constable, Giles. "The Historiography of the Crusades" in Angeliki E. Laiou, ed. The Crusades from the Perspective of Byzantium and the Muslim World (2001) Extract online.
- Illston, James Michael. 'An Entirely Masculine Activity'? Women and War in the High and Late Middle Ages Reconsidered (MA thesis, University of Canterbury, 2009) full text online
- Madden, Thomas F. ed. The Crusades: The Essential Readings (2002)
- Maier, C.T. "The roles of women in the crusade movement: a survey" Journal of medieval history 2004.
- Powell, James M. "The Crusades in Recent Research," The Catholic Historical Review (2009) 95#2 pp 313-19 in Project MUSE
- Rubenstein, Jay. "In Search of a New Crusade: A Review Essay," Historically Speaking (2011) 12#2 pp 25-27 in Project MUSE
- Primary sources
- Barber, Malcolm, Bate, Keith (2010). Letters from the East: Crusaders, Pilgrims and Settlers in the 12th–13th Centuries (Crusade Texts in Translation Volume 18, Ashgate Publishing Ltd)
- Bird, Jessalynn, et al. eds. Crusade and Christendom: Annotated Documents in Translation from Innocent III to the Fall of Acre, 1187-1291 (2013) excerpts
- Housley, Norman, ed. Documents on the Later Crusades, 1274–1580 (1996)
- Krey, August C. The First Crusade: The Accounts of Eye-Witnesses and Participants (1958)
- Shaw, M. R. B. ed.Chronicles of the Crusades (1963)
- Villehardouin, Geoffrey, and Jean de Joinville. Chronicles of the Crusades ed. by Sir Frank Marzials (2007)
|Look up Crusade in Wiktionary, the free dictionary.|
|Wikimedia Commons has media related to Crusades.|
|Wikisource has the text of the 1911 Encyclopædia Britannica article Crusades.|
- The Crusades, a virtual college course through Boise State University ed. by E. L. Knox.
- Crusades: A Guide to Online Resources, Paul Crawford, 1999.
- The Society for the Study of the Crusades and the Latin East—an international organization of professional Crusade scholars
- De Re Militari: The Society for Medieval Military History—contains articles and primary sources related to the Crusades