The Crusades were a series of religious wars sanctioned by the Latin Church in the medieval period, especially the campaigns in the Eastern Mediterranean with the aim of recovering the Holy Land from Islamic rule. The term "Crusades" is also applied to other church-sanctioned campaigns fought to combat paganism and heresy or to resolve conflict among rival Roman Catholic groups, or to gain political or territorial advantage. The term Crusades itself is early modern, modelled on Middle Latin cruciatae, and has in more recent times been extended to include religiously motivated Christian military campaigns in the Late Middle Ages.
The First Crusade arose after a call to arms in a 1095 sermon by Pope Urban II. Urban urged military support for the Byzantine Empire and its Emperor, Alexios I, who needed reinforcements for his conflict with westward migrating Turks who were colonising Anatolia. One of Urban's stated aims was to guarantee pilgrims access to the holy sites in the Eastern Mediterranean that were under Muslim control, but scholars disagree whether this was the primary motivation for Urban or most of those who heeded his call. Urban's wider strategy may have been to unite the Eastern and Western branches of Christendom, which had been divided since their split in the East–West Schism of 1054, and establish himself as head of the unified Church. The response to Urban's preaching by people of many different classes across Western Europe established the precedent for later Crusades. Volunteers became Crusaders by taking a public vow and receiving plenary indulgences from the church. Some were hoping for apotheosis at Jerusalem, or forgiveness from God for all their sins. Others participated to satisfy feudal obligations, gain glory and honour, or find opportunities for economic and political gain.
Many modern Historians have polarised opinions of the Crusaders' behaviour under Papal sanction. To some it was incongruous with the stated aims and implied moral authority of the papacy and the Crusades, to the extent that on occasions that the Pope excommunicated Crusaders. Crusaders often pillaged as they travelled, while their leaders retained control of much captured territory rather than returning it to the Byzantines. During the People's Crusade thousands of Jews were murdered in what is now called the Rhineland massacres. Constantinople was sacked during the Fourth Crusade rendering the reunification of Christendom impossible.
The Crusades had a profound impact on Western civilisation: they reopened the Mediterranean to commerce and travel (enabling Genoa and Venice to flourish); consolidated the collective identity of the Latin Church under papal leadership; and were a wellspring for accounts of heroism, chivalry and piety. These tales consequently galvanised medieval romance, philosophy and literature. But the Crusades also reinforced the connection between Western Christendom, feudalism, and militarism.
- 1 Terminology
- 2 Eastern Mediterranean
- 3 European campaigns
- 4 Aftermath
- 5 Further Information
- 6 Notes
Crusade is not a contemporaneous term: instead the terms iter for journey or peregrinatio for pilgrimage were used. Not until the word crucesignatus for one who was signed with the cross was adopted at the close of the twelfth century was specific terminology developed. The Oxford English Dictionary links the etymology of the word Crusade to the modern French croisade, Old French croisee, Provençal crozada, Spanish cruzada, Italian/medieval Latin crociata based on the verb "to cross," "a being crossed," "a crossing" or "marking with the cross," "a taking the cross." The Middle English equivalents were derived from old French; croiserie in the 13th–15th centuries and croisee in the 15–17th century. "Croisade" appeared in English c1575, and continued to be the leading form till c1760. By convention historians adopt the term for the Christian holy wars from 1095 but this does lead to a misleading impression of coherence in the early "Crusades".
The Crusades in the Holy Land are traditionally counted as nine distinct campaigns, numbered from the First Crusade of 1095–99 to the Ninth Crusade of 1271/2. This convention is used by Charles Mills in his History of the Crusades for the Recovery and Possession of the Holy Land (1820), and is often retained for convenience, even though it is somewhat arbitrary: The Fifth and Sixth Crusades led by Frederick II may be considered a single campaign, as can the Eighth Crusade and Ninth Crusade led by Louis IX.
Usage of the term "Crusade" may differ depending on the author. Giles Constable describes four different perspectives among scholars:
- Traditionalists restrict their definition of 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 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 subsumes 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 several 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 see Crusades as any and all holy wars connected with the Latin Church and fought in defence of their faith.
- Popularists 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.
Medieval Muslim historiographers such as Ali ibn al-Athir refer to the Crusades as the "Frankish Wars" (ḥurūb al-faranǧa حروب الفرنجة). 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.
The Islamic prophet Muhammad founded Islam in the Arabian Peninsula. The resulting unified polity in the seventh and eighth centuries led to a rapid expansion of Arab power. This influence stretched from the northwest Indian subcontinent, across Central Asia, the Middle East, North Africa, southern Italy, and the Iberian peninsula, to the Pyrenees. Tolerance, trade, and political relationships between the Arabs and the Christian states of Europe waxed and waned. For example, the Fatimid caliph al-Hakim bi-Amr Allah destroyed the Church of the Holy Sepulchre in Jerusalem, but his successor allowed the Byzantine Empire to rebuild it. During this period pilgrimages by Catholics to sacred sites were permitted, Christian residents in Muslim territories were given Dhimmi status, legal rights and legal protection. These Christians were allowed to maintain churches and marriages between faiths were not uncommon.  The various cultures and creeds coexisted and competed, but on returning to Western Europe Catholic pilgrims and merchants reported that the frontier conditions between the Syrian ports and Jerusalem were becoming increasingly inhospitable.
Beginning in the 8th century the recapture of the Iberian peninsula from the Muslims is known as the Reconquista. The turning point was reached in 1085 when Alfonso VI of León and Castile captured Toledo. In the same period Muslim Sicily was conquered by Norman adventurer Roger De Hauteville in 1091. At the other end of the Mediterranean Sea the Byzantine Empire also regained territory at the end of the 10th century, with Basil II spending most of his half-century reign in conquest. In Northern Europe, the Germans used Crusading as a method to expand Christianity and their territories at the expense of the non-Christian Slavs,
Europe in this period was immersed in power struggles on many different fronts. In 1054, centuries of attempts by the Latin Church to assert supremacy over the Patriarchs of the Eastern Empire led to a permanent division in the Christian church called the East–West Schism. Following the Gregorian Reform an assertive, reformist papacy attempted to increase its power and influence. Beginning around 1075 and continuing during the First Crusade, the Investiture Controversy was a power struggle between Church and state in medieval Europe over whether the Catholic Church or the Holy Roman Empire held the right to appoint church officials and other clerics. Antipope Clement III was an alternative pope for most of this period, and Pope Urban spent much of his early pontificate in exile from Rome. The result was intense piety, an interest in religious affairs, and religious propaganda advocating a just war to reclaim Palestine from the Muslims. The majority view was that non-Christians could not be forced to accept Christian baptism or be physically assaulted for having a different faith, although a minority believed that vengeance and forcible conversion were justified for the denial of Christian faith and government. Participation in such a war was seen as a form of penance that could counterbalance sin.
The status quo was disrupted by the invading Turks. Historians once, but no longer, consider the 1071 victory over the Byzantine army at the Battle of Manzikert as a decisive moment but it did presage significant expansion of Great Seljuk Empire into nearly all of Anatolia. One year later the Turks wrested control of Palestine from the Fatimids.
First Crusade (1096–1099) and aftermath
In 1095 at the Council of Piacenza, Byzantine Emperor Alexios I Komnenos requested military aid from Pope Urban II, probably in the form of a small body of mercenary reinforcements he could direct and control. Alexios had restored the Empire's finances and authority but he still faced a number of foreign enemies, particularly the migrating Turks who had colonised the sparsely populated areas of Anatolia. At the Council of Clermont later that year, Urban raised the issue again and preached for a Crusade. Historian Paul Everett Pierson asserts that Urban also hoped that aiding the Eastern Church would lead to its reunion with the Western under his leadership.
Almost immediately thereafter Peter the Hermit began preaching to thousands of mostly poor Christians, whom he led out of Europe in what became known as the People's Crusade. Peter had with him a letter he claimed had fallen from heaven instructing Christians to seize Jerusalem in anticipation of the apocalypse. In addition to the motivations of the landed classes, academic Norman Cohn has identified a "messianism of the poor" inspired by an expected mass apotheosis at Jerusalem. In Germany the Crusaders massacred Jewish communities. The Rhineland massacres were the first major outbreak of European antisemitism. In Speyer, Worms, Mainz and Cologne the range of anti-Jewish activity was broad, extending from limited, spontaneous violence to full-scale military attacks. Despite Alexios' advice to await the nobles, the People's Crusade advanced to Nicaea and fell to a Turkish ambush at the Battle of Civetot, from which only about 3,000 Crusaders escaped.
Both Philip I of France and Emperor Henry IV were in conflict with Urban and did not participate. However, members of the high aristocracy from France, western Germany, the Low countries and Italy were drawn to the venture, commanding their own military contingents in loose, fluid arrangements based bonds of lordship, family, ethnicity and language. Foremost amongst these was the elder statesman, Raymond IV, Count of Toulouse. He was rivalled by the relatively poor but martial Bohemond of Taranto and his nephew Tancred from the Norman community of southern Italy. They were joined by Godfrey of Bouillon and his brother Baldwin I of Jerusalem leading a loose conglomerate from Lorraine, Lotharingia and Germany. These five Princes were pivotal to the campaign which was also joined by a Northern French army led by Robert Curthose, Stephen, Count of Blois and Robert II, Count of Flanders.
The armies including non-combatants may have contained as many as 100,000 people, travelled eastward by land to Byzantium where they were cautiously welcomed by the Emperor. Alexius persuaded many of the princes to pledge allegiance to him and that their first objective should be Nicaea, which Kilij Arslan I had declared the capital of the Sultanate of Rum. Having already destroyed the earlier People's Crusade, the over confident Sultan left the city to resolve a territorial dispute enabling its capture after a Crusader siege and a Byzantine navel assault. This marked a high point in Latin and Greek co-operation and also the start of Crusader attempts to take advantage of political and religious disunity in the Muslim world. Crusader envoys sent to Egypt seeking an alliance.
The Crusades' first experience of the Turkish tactics of lightly armoured mounted archers was when an advanced party led by Bohemond and Duke Roberts was ambushed at Dorylaeum. The Normans resisted for hours before the arrival caused a Turkish withdrawal. After this the normadic Seljuks avoided the Crusade. The factionalism amongst the Turks that followed the death of Malik Shah meant they did not provide a united opposition. Instead Aleppo and Damascus had competing rulers. The three month march to Antioch was arduous with numbers reduced by the attrition of staravation, thirst and disease, combined with the decision of Baldwin to leave with 100 knights in order to carve out his own territory in Edessa. The Crusaders embarked on an eight-month siege of Antioch but lacked the resources to fully invest the city while the residents lacked the resources to repel the invaders. Eventually, Bohemond persuaded a tower guard in the city to open a gate and the Crusaders entered, massacring the inhabitants and pillaging the city. Sunni Islam had now recognised the threat and the sultan of Baghdad sent a relief force led by the Iraqi general Kerbogha. No assistance was provided by the Byzantines who had been told by the deserting Stephen of Blois that the cause was lost. Losing numbers through desertion and starvation in the besieged city the Crusaders attempted to negotiate surrender but this was rejected by Kerbogha who wanted to destroy them permanently. Morale within the city was boosted when Peter Bartholomew claimed to have discovered the Holy Lance. Bohemond recognised that the only option now was for open combat and launched a counterattack against the besiegers. Despite superior numbers Kerbogha's army, which was divided into factions and surprised by the motivation of the Franks, retreated and abandoned the siege. The Crusaders then delayed for months while they argued over who would have the captured territory. This only ended when news arrived that the Fatimid Egyptians had taken Jerusalem from the Turks and it became imperative to attack before they could consolidate their position. Bohemond remained in Antioch, retaining the city, despite his pledge that this would return to Byzantine control, while Raymond led the remaining Crusader army rapidly south along the coast to Jerusalem.
An initial attack on the city failed and with the Crusaders lack of resources the siege became a stalemate. However, the arrival of craftsman and supplies transported by the Genoese to Jaffa tilted the balance. Two large siege engines were constructed and the one commanded by Godfrey breached the walls on 15 July 1099. For two days the Crusaders proceeded to massacre the inhabitants and pillage the city. Historians now believe the accounts of the numbers killed have been exaggerated but the narrative did much to cement the Crusaders' reputation for barbarism  Godfrey further cemented the Frankish position by surprising Al-Afdal's relief force at Ascalon causing a retreat back to Egypt with the vizier fleeing by ship. At this point the Crusaders considered their pilgrimage complete and returned to Europe, leaving behind Godfrey with just 300 knights and 2,000 infantry to defend Palestine. Only Tancred of the other princes remained with the ambition to gain his own princedom.
The First Crusade established the first four Crusader states in the Eastern Mediterranean: the County of Edessa (1098–1149), the Principality of Antioch (1098–1268), the Kingdom of Jerusalem (1099–1291), and the County of Tripoli (1104 to 1289, although the city of Tripoli itself remained in Muslim control until 1109). The Armenian Kingdom of Cilicia originated before the Crusades, but it received kingdom status from Pope Innocent III and later became fully Westernised by the House of Lusignan. According to historian Jonathan Riley-Smith, these states were the first examples of "Europe overseas". They are generally known as outremer, from the French outre-mer ("overseas" in English).
On a popular level, the First Crusade unleashed a wave of impassioned, pious Catholic fury—expressed in the massacres of Jews that accompanied the Crusades and the violent treatment of the "schismatic" Orthodox Christians of the east. The Islamic world seems to have barely registered the Crusade, certainly there is limited written evidence before 1130. This may be in part due to a reluctance to relate Muslim failure but it is more likely to be the result of cultural misunderstanding. Al-Afdal and the Muslim world mistook the Crusaders for Byzantine mercenaries rather than religiously motivated warriors intent on conquest and settlement. In any case the Muslim world was divided between the Sunnis of Syria and Iraq and the Shia Fatimids of Egypt. Even the Turks were divided with rival rulers in Damascus and Aleppo. In Baghdad the Seljuk sultan vied with an Abbasid caliph in a Mesopotamian struggle. This gave the Franks a crucial opportunity to consolidate without any pan-Islamic counterattack.
Under the papacies of Calixtus II, Honorius II, Eugenius III and Innocent II smaller scale Crusading continued around the Crusader States in the early 12th century. The third decade saw campaigns by Fulk V of Anjou, the Venetians, Conrad III of Germany and the foundation of the Knights Templar. The period also saw the innovation of granting indulgences to those who opposed papal enemies, and this marked the beginning of politically motivated Crusades. The loss of Aleppo in 1128 and Edessa (Urfa) in 1144 to Imad ad-Din Zengi, governor of Mosul led to preaching for what subsequently became known as the Second Crusade. King Louis VII and Conrad III led armies from France and Germany to Jerusalem and also Damascus without winning any major victories. Bernard of Clairvaux, who had encouraged the Second Crusade in his preaching, was upset with the violence and slaughter directed towards the Jewish population of the Rhineland. Christian princes continued to make gains In the Iberian peninsula such as the King of Portugal, Afonso I, retaking Lisbon and Raymond Berenguer IV of Barcelona conquering the city of Tortosa In Northern Europe the Saxons and Danes fought against Wends in the Wendish Crusade, although no official papal bulls were issued authorising new Crusades. The Wends were finally defeated in 1162.
Egypt was ruled by the Shi'ite Fatimid dynasty from 969, independent from the Sunni Abbasid rulers in Baghdad and with a rival Shi'ite caliph— that is successor to the Muslim prophet Mohammad. Governance fell to the caliph's chief administrator called the vizier. From 1121 the system fell into murderous political intrigue and Egypt declined from its previous affluent state. This encouraged Baldwin III of Jerusalem to plan an invasion that was only halted by the payment by Egypt of a tribute of 160,000 gold dinars. In 1163 the deposed vizier, Shawar, visited Zengi’s son and successor, Nur ad-Din, atabeg of Aleppo in Damascus seeking political and military support. Historians have considered Nur ad-Din’s support as a visionary attempt to surround the Crusaders but he prevaricated and only responded when it became clear that the Crusaders might gain an unassailable foothold on the Nile. Nur al-Din sent his Kurdish general, Shirkuh, who stormed Egypt and restored Shawar. However, Shawar asserted his independence and allied with Baldwin’s brother and successor Amalric of Jerusalem. When Amalric broke the alliance in a ferocious attack, Shawar requested military support from Syria and Nur ad-Din sent Shirkuh again. Amalric retreated, but Shirkuh had Shawar executed and was appointed vizier. Barely two months later he died and was succeeded by his nephew, Yusuf ibn Ayyub, who has become known by his honorific ‘Salah al-Din’, ‘the goodness of faith’ which became westernised as Saladin. Nur al-Din died in 1174. He was the first Muslim to unite Aleppo and Damascus in the Crusade era. Some Islamic contemporaries promoted the idea that there was a natural Islamic resurgence under Zengi, through Nur al-Din to Saladin. Although, this wasn't as straight forward and simple as it appears. Saladin imprisoned all the Caliph's heirs preventing them from having children, as opposed to having them all killed which would have been normal practice, to extinguish the bloodline. Assuming control after the death of his overlord, Nur al-Din, Saladin had the strategic choice of establishing Egypt as an autonomous power or attempting to become the preeminent Muslim in the Eastern Mediterranean—he choose the latter 
As Nur al-Din’s territories fragmented after his death, Saladin legitimised his ascent through positioning himself as a defender of Sunni Islam subservient to the Caliph of Baghdad and Nur al-Din’s son and successor, As-Salih Ismail al-Malik. In his early ascendency he seized Damascus and much of Syria, but not Aleppo. After the building a defensive force to resist a planned attack by the Kingdom of Jerusalem that never materialised his first contest with the Latin Christians was not a success due to his overconfidence and tactical errors and he was defeated at the Battle of Montgisard.  Saladin established a domain stretching from the Nile to the Euphrates through as decade of politics, coercion and low level military action. He retook Jerusalem and won the Battle of Hattin in 1187. According to Benedict of Peterborough, Pope Urban III died of deep sadness on 19 October 1187 on hearing of the defeat. Pope Gregory VIII, issued a papal bull named Audita tremendi that proposed a further Crusade later numbered the third to recapture Jerusalem. Frederick I, Holy Roman Emperor died en-route to Jerusalem, drowning in the Saleph River, and few of his men reached the Eastern Mediterranean. In transit to Crusade, Richard I of England conquered Cyprus in 1191 in response to his sister and fiancée, who were travelling separately, being taken captive by the island's ruler, Isaac Komnenos. On arrival in the East, Richard quarrelled with Philip II of France who returned home, leaving most of his forces behind and Leopold V, Duke of Austria. Richard recaptured Acre after a long siege, travelled south along the Mediterranean coast, defeated the Muslims near Arsuf and recaptured the port city of Jaffa. He twice advanced to within a day’s march of Jerusalem before judging that he lacked the resources to successfully capture the City. This marked the end of Richard's Crusading career and was a calamitous blow to Frankish morale. A three-year truce was negotiated that allowed Catholics unfettered access to Jerusalem. Illness and politics in England forced Richard's departure, never to return, but Emperor Heny VI initiated the German Crusade to fulfil the promises made by his father, Frederick. Led by Conrad, Archbishop of Mainz, the army captured the cities of Sidon and Beirut. However, most of the Crusaders returned to Germany when Henry died.
Fourth Crusade & aftermath
The thirteenth century saw popular outbursts of ecstatic piety in support of the Crusades such as 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. Little reliable evidence survives for these events. However, they provide an indication of how hearts and minds could be engaged for the cause.
Innocent III also began preaching what became the Fourth Crusade in 1200, primarily in France, but also in England and Germany. After gathering in Venice the Crusade was used by Doge Enrico Dandolo and Philip of Swabia to further their secular ambitions. Dandolo's aim was expand Venice's power in the Eastern Mediterranean and Philip intended to restore his exiled nephew, Alexios IV Angelos, to the throne of Byzantium. The Crusaders were unable to pay the Venetians for a fleet when too few knights arrived in Venice, so they agreed to divert to Constantinople and share what could be looted as payment. As collateral the Crusaders seized the Christian city of Zara; Innocent was appalled, and excommunicated them. They also conquered Constantinople twice, after the initial success in taking the city, the original purpose of the campaign was defeated by the assassination of Alexios IV Angelos. In response the Crusaders captured the Constantinople again and this time sacked it, pillaging churches and killing many citizens. The Fourth Crusade never came within 1,000 miles of its objective of Jerusalem.
The Fourth Crusade established a Latin Empire in the east and allowed the partition of Byzantine territory by its participants. The Latin emperor controlled one-fourth of the Byzantine territory, Venice three-eighths (including three-eighths of the city of Constantinople), and the remainder was divided among the other Crusade leaders. This began the period of Greek history known as Frankokratia or Latinokratia ("Frankish [or Latin] rule"), when Catholic Western European nobles—primarily from France and Italy—established states on former Byzantine territory and ruled over the Orthodox Byzantine Greeks.[A] In the long run, the sole beneficiary was Venice.
Further Eastern Crusades
Following Innocent III's Fourth Council of the Lateran, Crusading resumed in 1217 against Saladin's Ayyubid successors in Egypt and Syria for what is classified the Fifth Crusade. Led by Andrew II of Hungary and Leopold VI, Duke of Austria, forces drawn mainly from Hungary, Germany, Flanders, and Frisia achieved little. Leopold and John of Brienne besieged and captured Damietta but an army advancing into Egypt was compelled to surrender. Damietta was returned and an eight-year truce agreed. Frederick II, Holy Roman Emperor was excommunicated for breaking treaty obligations with the Pope to Crusade. However his marriage to Isabella II of Jerusalem gave him a claim to the kingdom of Jerusalem and he finally arrived at Acre in 1228. Frederick was a most Muslim of Christian monarchs having grown up in Sicily, having a Muslim bodyguard and even a harem. His great diplomatic skills meant that the Sixth Crusade was largely negotiation supported by force. A peace treaty was agreed giving Latin Christians most of Jerusalem and a strip of territory from Acre, while the Muslims controlled their sacred areas. In return, an alliance was made with Al-Kamil, Sultan of Egypt, against all of his enemies of whatever religion. The treaty and suspicions about Frederick's ambitions in the region made him unpopular and was forced to return to his domains when they were attacked by Pope Gregory IX. While the Empire and Papacy were in conflict it often fell to secular leaders to campaign. What is sometimes known as the Barons' Crusade was led by Theobald I of Navarre and Richard of Cornwall combining forceful diplomacy and the playing of rival Ayyubid factions off against each other. This brief renaissance for Frankish Jerusalem was illusory, being dependent on Ayyubid weakness and division following the death of Al-Kamil.
In 1244 a band of Khwarezmian mercenaries travelling to Egypt to serve As-Salih Ismail, Emir of Damascus, seemingly of their own volition, captured Jerusalem en-route and defeated a combined Christian and Syrian army at the La Forbie. Louis IX, king of France, organised a Crusade, classified as the Seventh Crusade to attack Egypt in response, arriving in 1249. This was not a success. Louis was defeated at Mansura and captured as he retreated back to Damietta. Another truce was agreed for a ten-year period and Louis was ransomed. Louis remained in Syria until 1254 to consolidate the Crusader states. From 1265 to 1271, Baibars drove the Franks to a few small coastal outposts.
Division and failure
Late thirteenth century politics in the Eastern Mediterranean were complex with a number of powerful interested parties. The Mamluk sultan Baibars had three key objectives: the prevention of an alliance between the Latins and the Mongols, cause dissention between the Mongols particularly between the Golden Horde and the Persian Ilkhanate, and to maintain access to a supply of slave recruits from the Russian steppes. In this he developed diplomatic ties with Manfred, King of Sicily supporting him against the Papacy and Louis IX's brother Charles of Anjou. The Crusader states were disunified and various powers competed for influence. In the War of Saint Sabas Venice drove the Genoese from Acre to Tyre where they continued to trade happily with Baiber's Egypt. Indeed, Baibers negotiated free passage for the Genoese with Michael VIII Palaiologos, Emperor of Nicaea, the newly restored ruler of Constantinople.
The French, led by Charles, similarly sought to expand their influence seizing Sicily and Byzantine territory while also marrying his daughters to the Latin claimants to Byzantium. Charles executed one rival to the throne of Jerusalem and purchased the rights to Jerusalem from another to create his own claim to the throne. In 1270, Charles turned his brother King Louis IX's last Crusade, notionally known as the Eighth Crusade, to his own advantage by persuading Louis to attack his rebel Arab vassals in Tunis. Louis' army was devastated by disease i and Louis himself died at Tunis on 25 August. Louis' fleet returned to France leveing only Prince Edward and a small retinue to continue with what is known as the Ninth Crusade. Edward survived an assassination attempt organised by Beibars, 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 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 Michael VIII Palailogos deprived him of the resources of Sicily and Peter III of Aragon was proclaimed king of Sicily. Martin excommunicated Peter and called for an Aragonese Crusade in unsuccessful response. Charles died in 1285 having spent his life trying to amass a Mediterranean empire, and he and Louis saw themselves as God's instruments to uphold the papacy.
One factor in the Crusaders' decline was the disunity and conflict among Latin Christian interests in the eastern Mediterranean. Martin compromised the papacy by supporting Charles of Anjou, and tarnished its spiritual lustre with botched secular "Crusades" against Sicily and Aragon. The collapse of the papacy's moral authority and the rise of nationalism rang the death knell for Crusading, ultimately leading to the Avignon Papacy and the Western Schism. The mainland Crusader states of the outremer were extinguished with the fall of Tripoli in 1289 and Acre in 1291. Most remaining Latin Christians left for destinations in the Frankokratia or were killed or enslaved.
Crusades were expensive; as the number of wars increased, their costs escalated. Pope Urban II called upon the rich to help First Crusade lords such as Duke Robert of Normandy and Count Raymond of St. Gilles, who subsidised knights in their armies. The total cost to King Louis IX of France of the 1284–85 Crusades was estimated at six times the king's annual income. Rulers demanded subsidies from their subjects, and alms and bequests prompted by the conquest of Palestine were additional sources of income. The popes ordered that collection boxes be placed in churches and, beginning in the mid-twelfth century, granted indulgences in exchange for donations and bequests.
The military orders such as the Knights Hospitaller and the Knights Templar, provided Latin Christendom's first professional armies in support of the Latin Kingdom of Jerusalem and the other Crusader states. The Hospitallers (Order of Knights of the Hospital of Saint John of Jerusalem) had been founded in Jerusalem before the First Crusade but greatly enlarged its mission once the Crusades began. The Poor Knights of Christ (Templars) 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 across the Outremer. In time this developed into autonomous power in the region.
After the fall of Acre the Hospitallers first relocated to Cyprus, conquered and ruled Rhodes (1309–1522), Malta (1530–1798) and continue in existence to the present day. In 1322 the king of France suppressed the Knights Templar, ostensibly for sodomy, magic and heresy, but probably for financial and political reasons.
According to Jonathan Riley-Smith the Kingdom of Jerusalem was the first experiment in European colonialism creating a 'Europe Overseas' or Outremer. 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, creating profitable trading colonies in the eastern Mediterranean. This trade was sustained through the middle Byzantine and Ottoman eras, and the communities were often assimilated and known as Levantines or Franco-Levantines.[B]
The Crusades consolidated the papal leadership of the Latin Church, reinforcing the link between Western Christendom, feudalism and militarism manifesting itself in the habituating of the clergy to violence. The growth of the system of indulgences later was a catalyst for the Protestant Reformation in the early 16th century. The Crusades also had a role in the creation and institutionalisation of the military and Dominican orders as well as the Medieval Inquisition.
The assertiveness and the behaviour of the Crusaders appalled the Greeks and Muslims providing a lasting barrier between the Latin world and both the Islamic and Orthodox religions. It was an obstacle to the reunification of the Christian church and created a perception of the Westerners of being both aggressors and losers.
Historians argue that western Christian and Islamic interaction around the Mediterranean sea was a significant progressive factor in the development of European civilisation and a factor in the Renaissance. While Helen Nicholson argues that the increased contact between cultures the Crusades improved the perception of Islamic culture it is difficult to compare different spheres of influence. The art and architecture of the Outremer clearly demonstrates intra-cultural fusion but it is difficult to track illumination of manuscripts and castle design back to their sources. Textual sources are simpler and the translations made in Antioch are notable but they are considered secondary in importance to the works emanating from Iberia and the hybrid culture of Sicily. In addition Muslim libraries contained classical Greek and Roman texts which allowed Europe to rediscover pre-Christian philosophy. In contrast the Muslim world took little from the Crusaders beyond military tactics and did not take any real interest in European culture until the 16th century. Indeed, the Crusades were of little interest to the Muslim world: there was no history of the Crusades translated into Arabic until 1865 and no published work by a Muslim until 1899.
Jonathan Riley-Smith considers that much of the popular understanding of the Crusades derives from the novels of Walter Scott and the French histories by Joseph François Michaud. The Crusades provided an enormous amount of source material, stories of heroism and interest that underpinned growth in medieval literature, romance and philosophy.
Five major sources of information exist on the Council of Clermont that led to the First Crusade: the anonymous Gesta Francorum (The Deeds of the Franks, dated about 1100–01); Fulcher of Chartres, who attended the council; Robert the Monk, who may have been present, and the absent Baldric, archbishop of Dol and Guibert de Nogent. These retrospective accounts differ greatly. In his 1106–07 Historia Iherosolimitana, Robert the Monk wrote that Urban asked western Roman Catholic Christians to aid the Orthodox Byzantine Empire because "Deus vult" ("God wills it") and promised absolution to participants; according to other sources, the pope promised an indulgence. In these accounts, Urban emphasises reconquering the Holy Land more than aiding the emperor and lists gruesome offences allegedly committed by Muslims. Urban wrote to those "waiting in Flanders" that the Turks, in addition to ravaging the "churches of God in the eastern regions", 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". Although the pope did not explicitly call for the reconquest of Jerusalem, he called for military "liberation" of the Eastern Churches. After the 1291 fall of Acre, European support for the Crusades continued despite criticism by contemporaries, such as Roger Bacon, who believed them ineffective: "Those who survive, together with their children, are more and more embittered against the Christian faith".
During the 16th-century Reformation and Counter-Reformation, Western historians saw the Crusades through the lens of their own religious beliefs. Protestants saw them as a manifestation of the evils of the papacy, and Catholics viewed them as forces for good. Eighteenth-century Enlightenment historians tended to view the Middle Ages in general, and the Crusades in particular, as the efforts of barbarian cultures driven by fanaticism. These scholars expressed moral outrage at the conduct of the Crusaders and criticised the Crusades' misdirection—that of the Fourth in particular, which attacked a Christian power (the Byzantine Empire) instead of Islam. The Fourth Crusade had resulted in the sacking of Constantinople, effectively ending any chance of reconciling the East–West Schism and leading to the fall of the Byzantine Empire to the Ottomans. In The History of the Decline and Fall of the Roman Empire Edward Gibbon wrote that the Crusaders' efforts could have been more profitably directed towards improving their own countries. By the early Romantic period in the 19th century, that harsh view of the Crusades and their era had softened; scholarship later in the century emphasised specialisation and detail.
The 20th century produced three important histories of the Crusades: by Steven Runciman, Rene Grousset and a multi-author work edited by Kenneth Setton. Historians in this period often echoed Enlightenment-era criticism: Runciman wrote during the 1950s, "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". According to Norman Davies, the Crusades contradicted the Peace and Truce of God supported by Urban and reinforced the connection between Western Christendom, feudalism, and militarism. The formation of military religious orders scandalised the Orthodox Byzantines, and Crusaders pillaged countries they crossed on their journey east. Violating their oath to restore land to the Byzantines, they often kept the land for themselves. David Nicolle called the Fourth Crusade controversial in its "betrayal" of Byzantium. Similarly, Norman Housley viewed the persecution of Jews in the First Crusade—a pogrom in the Rhineland and the massacre of thousands of Jews in Central Europe—as part of the long history of anti-Semitism in Europe.
With the increasing focus on gender studies in the early 21st century, studies have been published on the topic of "Women in the Crusades" specifically. An essay collection on the topic was published in 2001, under the title Gendering the Crusades. In an essay on "Women Warriors", Caspi-Reisfeld comes the conclusion that "the most significant role played by women in the West was in maintaining the status quo", in the sense of noble women acting as regents of feudal estates while their husbands were campaigining. The presence of individual noble women in Crusades has been noted, such as Eleanor of Aquitaine (who joined her husband, Louis VII). The presence of non-noble women in the Crusading armies, as in medieval warfare in general, was mostly in the role of logistic support (such as "washerwomen"), while the occasional presence of women soldiers was recorded by Muslim historians.
The success of the First Crusade inspired 12th-century popes such as Celestine III, Innocent III, Honorius III and Gregory IX to call for military campaigns with the aim of Christianization of the more remote regions of northern and northeastern Europe. These campaigns are known as the Northern Crusades. The Wendish Crusade of 1147 saw Saxons, Danes and Poles enforce Catholic control over the tribes of Mecklenburg and Lusatia, Polabian Slavs (or "Wends"). Celestine III called for a Crusade in 1193, but when Bishop Berthold of Hanover responded in 1198, he led a large army to defeat and his death. In response Innocent III issued a bull declaring a Crusade and Hartwig of Uthlede, Bishop of Bremen along with the Brothers of the Sword brought all of the north-east Baltic under Catholic control. Konrad of Masovia gave Chelmno to the Teutonic Knights in 1226 as a base for Crusade against the local Polish princes. The Livonian Knights were defeated by the Lithuanians, so Gregory IX merged the remainder of the order into the Teutonic Order as the Livonian Order. By the middle of the century, the Teutonic Knights completed their conquest of the Prussians before conquering and converting the Lithuanians in the subsequent decades. The order also came into conflict with the Eastern Orthodox Church in the form of the Pskov and Novgorod Republics. In 1240 the Orthodox Novgorod army defeated the Catholic Swedes in the Battle of the Neva, and, two years later, they defeated the Livonian Order itself in the Battle on the Ice.
The Albigensian Crusade (1209–1229) was a campaign against heretics that Innocent III launched to eradicate Catharism, which had gained a substantial following in southern France. Cathar culture was brutally suppressed and the County of Toulouse passed under the direct control of Capetian France with the Treaty of Paris of 1229.
The Bosnian Crusade was a campaign against the Bosnian Church and was depicted as a campaign against Catharism (Bogomilism). However, it was also possibly motivated by Hungarian territorial ambitions. In 1216 a mission was sent to convert Bosnia to Rome but failed. In 1225, Honorius III encouraged the Hungarians to Crusade in Bosnia. This ended in failure after the Hungarians were defeated by the Mongols at the Battle of Mohi. From 1234 Gregory IX encouraged further Crusading, but again the Bosniaks repelled the Hungarians.
In the Iberian peninsula Crusader privileges were given to those aiding the Templars, Hospitallers and the Iberian orders that merged with the orders of Calatrava and Santiago. The Christian kingdoms pushed the Muslims back in frequent Papal endorsed Iberian Crusades from 1212 to 1265. The Emirate of Granada held out until 1492, at which point the Muslims and Jews were finally expelled from the peninsula.
Minor Crusading efforts lingered into the 14th century, while several Crusades were also 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 the 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. . It 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 westwards, 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 as 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 with 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 other vassals.
- Crusade cycle - Old French cycle of epic poems concerning the First Crusade
- List of principal Crusaders
- List of Crusader castles
- Art of the Crusades
- History of the Jews and the Crusades
- Miles Christianus ("Christian soldier")
- Religious war
- Arab–Byzantine wars (634–1050s)
- Byzantine–Ottoman Wars (1265–1479)
- Ottoman Wars in Europe (1453–1922)
- The Partitio terrarum imperii Romaniae is a valuable record of early-13th-century Byzantine administrative divisions (episkepsis) and family estates.
- (Frankolevantini; French Levantins, Italian Levantini, Greek Φραγκολεβαντίνοι, and Turkish Levantenler or Tatlısu Frenk leri). The term "Levantine" was used pejoratively for inhabitants of mixed Arab and European descent and for Europeans who adopted local dress and customs.
- Asbridge 2012, p. 40
- "Crusade". Oxford English Dictionary (3rd ed.). Oxford University Press. September 2005. (Subscription or UK public library membership required.)
- Davies 1997, p. 358
- Constable 2001, p. 12
- Riley-Smith 2009, p. 27
- Lock 2006, pp. 255–256
- Lock 2006, pp. 172–180
- Lock 2006, p. 167
- Davies 1997, pp. 362–364
- Constable 2001, pp. 12&ndas;15
- Determann 2008, p. 13
- Wickham 2009, p. 280
- Lock 2006, p. 4
- Hindley 2004, p. 14
- Pringle 1999, p. 157
- Findley 2005, p. 73
- Asbridge 2012, p. 28
- Bull 1999, pp. 18–19
- Mayer 1988, pp. 17–18
- Housley 2006, p. 31
- Mayer 1988, pp. 2–3
- Rubenstein 2011, p. 18
- Cantor 1958, pp. 8–9
- Riley-Smith 2009, pp. 10–11
- Riley-Smith 2005, pp. 8–10
- Asbridge 2012, p. 27
- Hindley 2004, p. 15
- Asbridge 2012, p. 34
- Pierson 2009, p. 103
- Hindley 2004, pp. 20–21
- Slack 2013, pp. 228–230
- Cohn 1970, pp. 61, 64
- Slack 2013, pp. 108–109
- Chazan 1996, p. 60
- Hindley 2004, p. 23
- Asbridge 2012, pp. 43–47
- Hindley 2004, pp. 30–31
- Asbridge 2012, pp. 52–56
- Asbridge 2012, pp. 57–59
- Asbridge 2012, pp. 21–22
- Asbridge 2012, pp. 59–61
- Asbridge 2012, pp. 70–71
- Asbridge 2012, pp. 72–82
- Asbridge 2012, pp. 146–153
- Asbridge 2012, pp. 96–103
- Asbridge 2012, pp. 104–106
- Asbridge 2012, p. 106
- Asbridge 2012, pp. 147–150
- "Outremer". Oxford English Dictionary (3rd ed.). Oxford University Press. September 2005. (Subscription or UK public library membership required.)
- Riley-Smith 2005, pp. 50–51
- Riley-Smith 2005, pp. 23–24
- Tyerman 2006, pp. 192–194
- Asbridge 2012, pp. 111–113
- Asbridge 2012, p. 114
- Housley 2006, p. 42
- Lock 2006, pp. 144–145
- Lock 2006, pp. 146–147
- Riley-Smith 2005, pp. 104–105
- Lock 2006, p. 144
- Hindley 2004, pp. 71–74
- Hindley 2004, pp. 77–85
- Hindley 2004, p. 77
- Hindley 2004, pp. 75–77
- Villegas-Aristizabal 2009, pp. 63–129
- Lock 2006, p. 148
- Lock 2006, p. 213
- Lock 2006, pp. 55–56
- Asbridge 2012, pp. 266–268
- Asbridge 2012, pp. 272–275
- Asbridge 2012, pp. 282–286
- Asbridge 2012, pp. 287–288
- Asbridge 2012, p. 292
- Asbridge 2012, pp. 307-308
- Asbridge 2012, p. 322
- Asbridge 2012, pp. 343–357
- Asbridge 2012, p. 367
- Tyerman 2007, pp. 35–36
- Asbridge 2012, pp. 429–430
- Asbridge 2012, p. 509
- Asbridge 2012, pp. 512–513
- Lock 2006, p. 155
- Asbridge 2012, pp. 533–535
- Tyerman 2006, pp. 502–508
- Davies 1997, pp. 359–360
- Lock 2006, pp. 158–159
- Asbridge 2012, p. 530
- Runciman 1951, p. 480
- Davies 1997, p. 360
- Lock 2006, pp. 168–169
- Riley-Smith 2005, pp. 179–180
- Hindley 2004, pp. 561–562
- Asbridge 2012, pp. 566–571
- Asbridge 2012, p. 569
- Asbridge 2012, p. 573
- Asbridge 2012, p. 574
- Asbridge 2012, pp. 574–576
- Tyerman 2006, pp. 770–775
- Hindley 2004, pp. 194–195
- Lock 2006, p. 178
- Tyerman 2006, pp. 816–817
- Asbridge 2012, pp. 628–630
- Asbridge 2012, pp. 643–644
- Runciman 1958, p. 88
- Lock 2006, p. 122
- Tyerman 2006, pp. 820–822
- Riley-Smith 2009, pp. 43–44
- Riley-Smith 2009, p. 44
- Nicholson 2001
- Asbridge 2012, p. 168
- Asbridge 2012, pp. 169–70
- Davies 1997, p. 359
- Housley 2006, pp. 152–154
- "Levantine". Oxford English Dictionary (3rd ed.). Oxford University Press. September 2005. (Subscription or UK public library membership required.)
- Krey 2012, pp. 280–281
- Housley 2006, pp. 147–149
- Strayer 1992, p. 143
- Asbridge 2012, pp. 667–668
- Nicholson 2004, p. 96
- Asbridge 2012, pp. 667–668
- Nicholson 2004, pp. 93–94
- Nicholson 2004, p. 95
- Strack 2012, pp. 30–45
- Riley-Smith & Riley-Smith 1981, p. 38
- Rose 2009, p. 72
- Lock 2006, p. 257
- Lock 2006, p. 259
- Lock 2006, p. 261
- Lock 2006, p. 266
- Lock 2006, p. 269
- Kolbaba 2000, p. 49
- Vasilev 1952, p. 408
- Nicolle 2011, p. 5
- Housley 2006, pp. 161–163
- Caspi-Reisfeld 2002, p. 98
- Owen 1993, p. 22
- Nicholson 1997, p. 337
- Davies 1997, p. 362
- Lock 2006, p. 96
- Lock 2006, p. 103
- Lock 2006, pp. 221–222
- Lock 2006, pp. 104, 221
- Riley-Smith 1999, p. 4
- Lock 2006, pp. 163–165
- Lambert 1977, p. 143
- Lock 2006, p. 211
- Lock 2006, pp. 187–188
- Lock 2006, pp. 195–196
- Lock 2006, p. 199
- Davies 1997, p. 448
- Lock 2006, p. 200
- Lock 2006, pp. 201–202
- Lock 2006, pp. 202–203
- Lock 2006, p. 204
- Davies 1997, pp. 544–545
- Asbridge, Thomas (2012). The Crusades: The War for the Holy Land. Simon & Schuster. ISBN 978-1-84983-688-3.
- Bull, Marcus (1999). "Origins". In Riley-Smith, Jonathan. The Oxford History of the Crusades. Oxford University Press. ISBN 0-19-280312-3.
- Cantor, Norman F (1958). Church. Kingship, and Lay Investiture in England: 1089–1135. Princeton University Press. ISBN 1-4008-7699-0.
- Caspi-Reisfeld, Keren (2002). "Women Warriors during the Crusades 1095–1254". In Edington, Susan B.; Lambert, Sarah. Gendering the Crusades. Columbia University Press. ISBN 978-0-231-12598-7.
- Chazan, Robert (1996). European Jewry and the First Crusade. U. of California Press. p. 60. ISBN 978-0-520-91776-7. Retrieved 2016-10-04.
- Cohn, Norman (1970). The Pursuit of the Millennium. Oxford University Press. ISBN 978-0-19-500456-4.
- Constable, Giles (2001). "The Historiography of the Crusades". In Laiou, Angeliki E.; Mottahedeh, Roy P. The Crusades from the Perspective of Byzantium and the Muslim World. Dumbarton Oaks. pp. 1–22. ISBN 978-0-88402-277-0. Retrieved 2016-10-04.
- Davies, Norman (1997). Europe – A History. Pimlico. ISBN 0-7126-6633-8.
- Determann, J. (2008). "The Crusades in Arabic Schoolbooks". Islam and Christian-Muslim Relations. Routledge. ISSN 0959-6410.
- Findley, Carter Vaughan (2005). The Turks in World History. Oxford University Press. ISBN 0-19-516770-8.
- Hindley, Geoffrey (2004). The Crusades: Islam and Christianity in the Struggle for World Supremacy. Carrol & Graf. ISBN 0-7867-1344-5.
- Housley, Norman (2006). Contesting the Crusades. Blackwell Publishing. ASIN 1405111895. ISBN 1-4051-1189-5.
- Kolbaba, T. M. (2000). The Byzantine Lists: Errors of the Latins. University of Illinois. ISBN 0-252-02558-X.
- Krey, August C. (2012). The First Crusade: The Accounts of Eye-Witnesses and Participants. Arx Publishing. ISBN 978-1-935228-08-0.
- Lambert, Malcolm D. (1977). Medieval Heresy: Popular Movements from Bogomil to Hus. Holmes & Meier Publishers. ISBN 978-0-8419-0298-5.
- Lock, Peter (2006). Routledge Companion to the Crusades. Routledge. ISBN 0-415-39312-4.
- Mayer, Hans Eberhard (1988). The Crusades (Second ed.). Oxford University Press. ISBN 0-19-873097-7.
- Nicholson, Helen (1997). "Women on the Third Crusade". Journal of Medieval History. 23 (4): 335. doi:10.1016/S0304-4181(97)00013-4.
- Nicholson, Helen J. (2001). The Knights Hospitaller. Boydell & Brewer. ISBN 978-0-85115-845-7. Retrieved 2016-10-04.
- Nicholson, Helen (2004). The Crusades. Greenwood Publishing Group. ISBN 978-0-313-32685-1.
- Nicolle, David (2011). The Fourth Crusade 1202–04: The Betrayal of Byzantium. Osprey Publishing. ISBN 1-84908-821-7.
- Owen, Roy Douglas Davis (1993). Eleanor of Aquitaine: Queen and Legend. Blackwell Publishing. ISBN 90-474-3259-2.
- Pierson, Paul Everett (2009). The Dynamics of Christian Mission: History Through a Missiological Perspective. WCIU Press. ISBN 978-0-86585-006-4. Retrieved 2016-10-04.
- Pringle, Denys (1999). "Architecture in Latin East". In Riley-Smith, Jonathan. The Oxford History of the Crusades. Oxford University Press. ISBN 0-19-280312-3.
- Riley-Smith, Jonathan (1999). Riley-Smith, Jonathan, ed. The Crusading Movement and Historians. The Oxford History of the Crusades. Oxford University Press. ISBN 0-19-280312-3.
- Riley-Smith, Jonathan (2005). The Crusades: A Short History (Second ed.). Yale University Press. ISBN 0-300-10128-7.
- Riley-Smith, Jonathan (2009). What Were the Crusades?. Palgrave Macmillan. ISBN 978-0-230-22069-0.
- Riley-Smith, Louise; Riley-Smith, Jonathan (1981). The Crusades: Idea and Reality, 1095–1274. Documents of Medieval History. 4. E. Arnold. ISBN 0-7131-6348-8.
- Rose, Karen (2009). The Order of the Knights Templar. CreateSpace Independent Publishing Platform. ISBN 978-1-4486-5190-0.
- Rubenstein, Jay (2011). Armies of Heaven: The First Crusade and the Quest for Apocalypse. Basic Books. ISBN 0-465-01929-3.
- Runciman, Steven (1951). A History of the Crusades: The Kingdom of Acre and the Later Crusades (reprinted 1987 ed.). Cambridge University Press. ISBN 978-0-521-06163-6.
- Runciman, Steven (1958). The Sicilian Vespers. A History of the Mediterranean World in the Later Thirteenth Century (reprinted 1987 ed.). Cambridge University Press. ISBN 0-521-43774-1.
- Slack, Corliss K (2013). Historical Dictionary of the Crusades. Scarecrow Press. pp. 108–09. ISBN 978-0-8108-7831-0. Retrieved 2016-10-04.
- Strack, Georg (2012). "The Sermon of Urban II in Clermont and the Tradition of Papal Oratory" (PDF). Medieval Sermon Studies. 56 (30#1): 30–45. doi:10.1179/1366069112Z.0000000002.
- Strayer, Joseph Reese (1992). The Albigensian Crusades. University of Michigan Press. ISBN 0-472-06476-2.
- Tyerman, Christopher (2006). God's War: A New History of the Crusades. Belknap Press. ISBN 978-0-674-02387-1.
- Tyerman, Christopher (2007). The Crusades. Sterling Publishing Company, Inc. pp. 111–. ISBN 978-1-4027-6891-0. Retrieved 2016-10-04.
- Vasilev, Aleksandr Aleksandrovich (1952). History of the Byzantine Empire: 324–1453. University of Wisconsin Press.
- Villegas-Aristizabal, 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. Penguin Books. ISBN 978-0-14-311742-1.
- Asbridge, Thomas (2005). The First Crusade: A New History: The Roots of Conflict between Christianity and Islam. ISBN 0-19-518905-1.
- Daniel, Norman (1979). The Arabs and Mediaeval Europe. Longman Group Limited. ISBN 0-582-78088-8.
- Hodgson, Natasha (2007). Women, Crusading and the Holy Land in Historical Narrative. Boydell.
- Kahf, Mohja (1999). Western Representations of the Muslim Women: From Termagant to Odalisque. U of Texas Press. ISBN 978-0-292-74337-3.
- Maier, Christoph T. (March 2004). "The roles of women in the Crusade movement: a survey". Journal of Medieval History. 30 (1): 61–82. doi:10.1016/j.jmedhist.2003.12.003.
- Phillips, Jonathan. Holy Warriors: A Modern History of the Crusades (2010)
- Riley-Smith, Jonathan (ed.) The Oxford Illustrated History of the Crusades Paperback, Oxford University Press (2001).
- Riley-Smith, Jonathan. The Crusades: A history (Bloomsbury Publishing, 2014)
- Runciman, Steven. A History of the Crusades (3 vols. 1951–1954)
- Setton, Kenneth ed., A History of the Crusades, University of Wisconsin Press (6 vols., 1969–1989; online edition (wisc.edu))
- Tolan, John; Veinstein, Gilles; Henry, Laurens (2013). Europe and the Islamic World: A History. Princeton University Press. ISBN 978-0-691-14705-5.
- 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.
- 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
- von Güttner-Sporzyński, Darius. "Recent Issues in Polish Historiography of the Crusades" in Judi Upton-Ward, The Military Orders: Volume 4, On Land and by Sea (2008) available on Researchgate, available on Academia.edu
- 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)
- 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)