Conflicts of Ideology in Christian and Muslim Holy War

David Levine

The holy wars of Christianity and Islam, crusade and jihad respectively, represent a conflict of ideology between two Abrahamic faiths that would be reignited with the First Crusade in 1096. What makes them different is not the wars' necessity in their respective societies, but their origins. Jihad is explicitly referred to and justified in the Qur'an and crusading came into thought nearly a thousand years after the beginning of Christianity. Practice and execution also differentiate them. For a religious contrast, where Christians viewed Muslims as worshipping a false god through a false prophet, the Muslims were more concerned with the Christians' use of anthropomorphic imagery for veneration. Thus the difference in these two ideals can be seen: crusading ideology began to take shape in the late 11th century, and was driven by a politically minded, centralized papacy; jihad existed from the beginnings of Islam, and was driven by secular leaders using religious means to their political ends. The parallels of these respective holy wars as unifying forces in otherwise fragmented societies obscure the differences in origin and execution between them, and if not for this fragmentation and various other factors neither may have been employed at all.

Historians have defined crusading broadly. For Jonathan Riley-Smith, there must be vows taken by the crusaders with papal authorization that are fulfilled through penitential warfare. Similarly, Partner argues that crusading is defined by the focus on Jerusalem and the support of Christians in the east. Prior to the formation of semi-official crusading patterns, other popes had made calls for one or more aspects of crusade that would later be compiled into official crusading guidelines by Pope Innocent III. Pope John VIII, in defense of Rome from Muslim armies, promised spiritual rewards for those who would die in defense of the church. Pope Leo IV did the same, as did Pope Alexander II. The ideology of Christian holy war was also abortively proposed by the Byzantine Empire over a century before the first Crusade, failing due to inopportune political changes and the clerical resistance.

Remission of sins was a particular focus of pre-crusading ideological patterning. According to Cowdrey, "In the eleventh century...penance was still being imposed under an older system [from] Carolingian times." There was little differentiation between what penances were appropriate for what sins, and often the masses were unsure of the remission of their sins. For the upper classes, there was a choice between endowment of a monastery, becoming a monk, or pilgrimage to holy sites like Rome and Jerusalem.

Prior to Gregory VII's reforms, the idea of warfare as penitence was unthinkable; after, armed pilgrimage became an outlet for knightly penitence, channeling the violent life of European knighthood into armies of Christ. This shift in ideology was enabled by the writings of Augustine of Hippo. Augustine sought to rationalize the violence around him, proposing that war could only be just if fought defensively, in the name of the church, and as a last option. With his reforms, Gregory VII successfully formed the ideological basis that would be later used by Urban II in calling the First Crusade: holy war was now a functional theory involving rationalization for just war, spiritual benefits, and legitimacy gained from papal leadership. The Church had developed direct authority over newly sanctioned knights. Thus with the justification of a saint and new, albeit broad definitions, crusading as an ideal became more than bits and pieces of theology and developed into a definitive formula that Urban II used only twenty years later.

Jihad draws its theological justification directly from the Qur'an. In Arabic, the word jihad translates as "striving" or "expenditure of effort;" jihad may even seem inconsequential and unimportant, given the word only appears in the Qur'an four times. Christian holy war held violence as the last resort; jihad was a "doctrine of spiritual effort, of which military action is only one possible manifestation." Jihad is and was an effort in the name of Allah, restricted by morality outlined by Allah in the Qur'an. Jihad evolved in the early Muslim community as a defensive stance around Muhammad, who had experienced a revelation that it was a sacred duty of Muslims to defend themselves when faced by pagan and polytheistic oppressors. When Muhammad was forced to flee to Medina his party had to raid caravans to survive. Those who participated in these raids believed themselves mujahedeen, those who struggle in the path to God. During this time, jihad was one of the chief duties of a Muslim. . The Qur'an speaks in sura 9 of Allah offering heavenly rewards for those who fight "idolaters and polytheists." This struggle was meant to be continuous until all peoples were united in Islam or had accepted the status of dhimmis, or protected minorities. In verses 39-40, the last verses to mention jihad in the Qur'an, regulations are set for how, when and why jihad must be waged. The regulations regarding jihad are explicitly defensive, being restrained by "right intention" and "proportionality." These verses were revealed to Muhammad during the Medinan period, when "violence was not only necessary for the defense of the Muslim community, but also unavoidable." As Donner states, "[Mujahedeen] may thus correspond to the early Christians who viewed themselves as 'soldiers of Christ'...." Like crusading, jihad saw soldiers fighting in the name of God (or Allah), but the comparison is faulty because the Muslim soldiers answered directly to Allah whereas the Christian soldiers needed intercession from the Church for their sins to be forgiven. The distinction highlights the doctrinal differences in practice: the Church was necessary because there was no precedent for remission of sins through struggle in Christian gospel as there was in Islam. The closest similarity seen is that both holy wars gave hope of martyrdom and heavenly reward for those who fought and died in the service of God.

The societies that produced jihad and crusade must be analyzed. Carolingian government dominated Europe west of the Byzantine Empire, encompassing modern-day Italy, Germany and France, and the Carolingian dynasty was the beginning of the Holy Roman Empire. European society was held together for the most part by the leaders of the Holy Roman Empire and the people were protected by it; but once this semi-centralized government collapsed, the region split into minor monarchies and duchies. Once public authority disintegrated, lords and counts began turning to their own interests. Cowdrey states, "In France, the post-Carolingian breakdown of authority, and the gravest manifestations of feudal anarchy, seem to have reached their nadir in the generation following the year 1000." This lack of central authority would last until the papal reformation of Gregory VII. Urban II, when preaching the First Crusade, was far more in-tune with the needs and wants of a fragmented European society than any of his predecessors had been: his preachings struck the perfect note that would unite Western Europe to the greatest extent for over a century. His greatest achievement may have been his explicit break from precedent, preaching the First Crusade as an armed pilgrimage rather than an unarmed one. Bachrach repeats this in the context of remission of sin, stating that Urban "had his finger on the pulse of the western nobility with regard to their aching need to find redemption for their sinful lives."

Between the Carolingian collapse and Gregorian Reform, the clergy and laypeople needed to be protected from the wars and infighting of local lords and knights: this protection would be guided by the Peace of God. As Cowdrey writes, the original purpose of this was to place those who could not protect themselves or their property under ecclesiastical protection, such as religious persons or the poor. Measures such as this had been around for a while, but what set the Peace of God apart was that its legitimacy came from the Church, not kings. The Peace of God set the stage for the Truce of God, which, beginning in 1027 explicitly forbid all violence at certain times, such as holidays or saints' days. One account written in 1083 by the bishop of Cologne lays out the increasing number of days on which violence and fighting was prohibited. Urban would later lean on the Peace and Truce of God in calling on European nobles to stop fighting with each other. Ultimately, it was the precedent set by these notions that allowed for the unprecedented scope and spread of Urban's message. These events certainly helped cement a precedent that Urban would later draw upon. Without these interceding steps, laymen and counts could have considered crusading alike as just another attempt by the Church of lording over the secular authorities; with the fall of the Carolingian dynasty the Church would obtain an opening for power, and with the Peace and Truce of God they would exert it.

The newfound power the Church held in Western Europe was hampered by the lack of a central leader. As mentioned above, before Pope Gregory VII the papacy was at best the first amongst equals of bishoprics. Gregory, during what historians have called "The Investiture Disputes," took on his secular contemporaries for supreme influence over the course of Europe's future. The papacy had a very clear view of their role in society: according to Brooke, the papacy's view was a unified Christian society with all authority coming from God: while spiritual and temporal power could coexist on the earth, ultimate supremacy belonged to the spiritual authorities because of their control over the salvation of men's souls. Within fifty years, the Investiture Disputes were over and the Church emerged the clear victor: Gregory's dream was fulfilled, and he would make the Church the center of the world through war.

His plans for crusading would never come to fruition in his lifetime though. Gregory's weaknesses were his reasons for calling a crusade. He called for the reunion of the Eastern and Western Churches and crusade against Robert Guiscard, the Norman duke of Apulia and Calabria. These reasons lacked a personal connection for most of Western Europe. In Rome, Gregory was constantly fighting the Normans for control over southern Italy; but in France and Germany, there was no concern for the pope's predicament. The nobles of Western Europe were too busy fighting amongst themselves to care much about the troubles of the pope. The reunion of the Eastern and Western Churches, an ostensibly erstwhile goal, failed to recognize the deep mistrust of Western Christians for their Eastern counterparts. As Menache states, "The existence of a common Christian faith did not bridge the sociocultural gap with Byzantium..." Pope Urban's preaching of the First Crusade took this suspicion into account in making the final goal Jerusalem. Pope Gregory saw European society for what it was: a politically fragmented continent of constantly feuding monarchies and duchies aching for a new path to salvation for their violent and sinful lives. He also saw a chance for reconciliation between the two churches after the Battle of Manzikert when the Byzantine army was utterly destroyed by Alp Arslan's army of Seljuk Turks. His failure to understand both the suspicion of the Eastern Church in the west and how new and unprecedented papal power was viewed, became the final step before Urban's success in preaching the First Crusade, and the political fragmentation of Western Europe would produce the need for an armed pilgrimage to unite them under the Peace and Truce of God.

There are similarities between the political fragmentation of Western Europe and the divisions amongst Muslims in the East. The biggest difference is that the Muslims' divisions were rooted deeply in religion. From the caliphate of 'Ali, the fourth rightly guided caliph and the son-in-law of Muhammad onwards, the Sunni-Shiite split between Muslims became an unbridgeable gap underlying any superficially political divisions. In the Kitab al-Jihad, Ali b. Tahir al-Sulami writes: "God dispersed their unit, split up their togetherness, threw enmity and hatred between them and tempted their enemies to snatch their country from their grasp and [so] cure their hearts of them." He blames Muslim problems after the fall of Jerusalem to the Franks on internal friction that came after the "caliphs ignored this responsibility" of waging jihad as Muhammad had ordered. Al-Sulami believed that jihad was the only way to unify Muslims and that the Franks taking Jerusalem was a wake-up call to bring Muslims back to obedience under Islam. The jihad waged by the prophet, his companions, and his successors formed the Islamic empire and spread Islam from North Africa to the borders of the Byzantine Empire, and that determination would be required to expel the Franks from their lands. Unfortunately, beyond al-Sulami there are few Muslim sources available that speak of the reaction to the First Crusade in the Muslim world and even fewer that have been translated; but reaction was apathetic at best. According to Partner:

There was a reaction to the Crusades among the Damascus ulama or learned class, during the first decade of the [twelfth] century, and that the call for a jihad played a part in this reaction. But it is hard to find a Muslim government saying that it was executing a jihad against the Franks, before the 1120's.

The apathy towards uniting shown by Muslims is analogous to the warring kingdoms of Western Europe before the First Crusade. What makes them different is the message necessary to make unification possible. In Christian lands, only a political entity could unite a region already united through religion, and in Muslim lands both political and religious unity was required.

The Preaching of the First Crusade relied heavily on precedents of Pope Gregory VII's fusion of just war, papal involvement, and remission of sin into a single message. The reasons for the failure of Gregory's crusading plans have been addressed above. In Pope Urban II the papacy found the right messenger and style for preaching a successful crusade. Urban recombined religion and war, the two most "vital and deeply cherished interests of the western people," into a crusading institution. From accounts such as the Gesta Francorum and other historians who relied on it develops a clear picture of Urban's message and style. Urban is said to have used guilt, an emphasis on rhetoric and theater, and an explicit focus on Jerusalem as the crusaders' goal. Guibert of Nogent says that Urban also emphasized armed pilgrimage as the only source of remission of sins for the knights of Christian Europe. Urban was also more cognizant of the wants of the French nobility that would form a large contingent in the First Crusade, which Gregory had neglected: to Urban, only "leaders of French chivalry" could lead this expedition. Munro gives a thorough topic-by-topic description of the themes Urban would have used to rouse Western Christians to crusade. Public exhortation like Urban's speech at Clermont was common in the Islamic world, and Muslim preachers of jihad used this as their medium. Preachers portrayed jihad as a religious struggle against crusaders and connected jihad with the Sunni revival under the Zengids, as al-Sulami's work indicates.

The newly resplendent papacy in Europe manufactured crusading as a threefold means to demonstrate its newfound power, to unite the warring nobles of Europe, and to recapture Jerusalem against the Muslim nonbelievers who "practiced the worship of a false god." Muslim leaders who took up the banner of jihad similarly sought to unite all or some of the Muslim lands, and after the fall of Jerusalem, to reconquer the third holiest city in Islam from the infidels who, as 'Imad al-Din al-Isfahani wrote, "...prepared war, seeking to espouse death; they launched themselves across the sea, wanting their fame to be on everybody's lips." The way the Muslims perceived the crusades greatly influenced their response as well. Muslims did not see the crusades the same way Western Christians did. To Muslims, the crusades were a "disparate series of battles against Frankish invaders." In this way, little separated these new Frankish invaders from other Muslim sultanates and caliphates that had been invading and conquering each others lands for centuries. Apathy would lead to nearly 40 years of Frankish rule with little organized Muslim response. Not until Imad ad-Din Zengi would Muslims begin to unite in any meaningful way under a banner of jihad. For Muslims, Zengi would be the step that Gregory was for Christians: Muslims needed a figure to promote a new way of unifying the Islamic world, and Zengi would be that figure. What is clear is that in both Muslim and Western Christian society, only great expeditions like jihad and crusade would unite their respectively fragmented regions. Both cases show precedent being built upon, such as Pope Urban II leaning on Pope Gregory VII's ideas and the Zengids using al-Sulami's preachings as political legitimization for jihad. Though origins differ between the holy wars of Christianity and Islam, the use of holy war in these societies illustrates the necessity of holy war in the reunification of the religiously fractured Islamic realm and the politically fractured lands of Western Christianity.


Allen, S. J., and Emilie Amt, eds. The Crusades: A Reader. Readings in Medieval Civilizations and Cultures, VIII. Toronto: University of Toronto Press, 2010.

Al-Sulami. "Kitab al-Jihad." 30 and 36. Zahiriyya Damascus.

Azzam, Abdul Rahman. Saladin. N.p.: Pearson Education Limited, 2009.

Bachrach, Bernard S. "Papal War Aims in 1096: The Option Not Chosen." In In Laudem Hierosolymitani: Studies in Crusades and Medieval Culture in Honour of Benjamin Z. Kedar, by Iris Shagrir, Roni Ellenblum, Jonathon Simon Christopher Riley-Smith, and B.Z. Kedar, 319-341. Crusades - Subsidia 1. Burlington: Aldershot England, 2007.

Berger, Pamela. "Crusade and Jihad: The Wars Known as Holy." Religion and the Arts 5, no. 4 (2001): 484-494. JSTOR.

Berkey, Jonathan P. Popular Preaching and Religious Authority in the Medieval Islamic Near East. Seattle: University of Washington Press, 2001.

Boyd, Catherine E. "The Gregorian Reform." In The Gregorian Epoch: Reformation, Revolution, Reaction?, by Schafer Williams, 75-86. Boston: D.C. Heath and Company, 1964.

Brooke, C.N.L., M.A. The Investiture Disputes. Aids for Teachers 4. 1958. Reprint, London: The Historical Association, 1966.

Brooke, Zachary N. "Lay Investiture and Its Relation to the Conflict of Empire and Papacy." In The Gregorian Epoch: Reformation, Revolution, Reaction?, by Schafer Williams, 25-36. Boston: D.C. Heath and Company, 1964.

Christie, Niall. "A Translation of Extracts from the Kitab al-Jihad of 'Ali ibn Tahir Al-Sulami." Journal Asiatique, no. 254 (1966): 206-22.

Christie, Niall, and Deborah Gerish. "Parallel Preachings: Urban II and al-Sulami." Al-Masaq: Islam and the Medieval Mediterranean 15, no. 2 (2003): 139-148.

Claster, Jill N. Sacred Violence: The European Crusades to the Middle East, 1095-1396. Toronto: University of Toronto Press, 2009.

Cowdrey, H.E.J. "The Genesis of the Crusades: The Springs of Western Ideas of Holy War." In The Holy War, edited by Thomas Patrick Murphy, 9-32. N.p.: Ohio State University Press, 1976.

———. "The Peace and Truce of God in the Eleventh Century." Past and Present 46 (February 1970): 42-67. JSTOR.

———. "Pope Gregory VII's 'Crusading' Plans of 1074." In Outremer: Studies in the History of the Crusading Kingdom of Jerusalem, edited by Joshua Prawer, B.Z. Kedar, Hans Eberhard Mayer, R.C. Smail, and Yad Yitshak Ben-Tsevi, 27-40. Jerusalem: Yad Izhak Ben-Zvi Institute, 1982.

———. Pope Gregory VII, 1073-1085. New York: Oxford University Press, 1998.

Donner, Fred M. "The Sources of Islamic Conceptions of War." In Just War and Jihad: Historical and Theoretical Perspectives on War and Peace in Western and Islamic Traditions, edited by John Kelsay and James Turner Johnson, 31-70. Westport: Greenwood Press, 1991.

Gabrieli, Francesco. Arab Historians of the Crusades. Translated by E.J. Costello. Berkeley: University of California Press, 1969.

Gesta Francorum. Edited and translated by Rosalind Hill. London: Thomas Nelson and Sons, 1962.

Hamilton, Bernard. "Pope John X (914-928) and the Antecedents of the First Crusade." In In Laudem Hierosolymitani: Studies in Crusades and Medieval Culture in Honour of Benjamin Z. Kedar, by Iris Shagrir, Roni Ellenblum, Jonathon Simon Christopher Riley-Smith, and B.Z. Kedar, 309-318. Crusades - Subsidia 1. Burlington: Aldershot England, 2007.

Hillenbrand, Carole, comp. The Crusades: Islamic Perspectives. Edinburgh: Edinburgh University Press, 1999.

Johnson, James Turner. "Historical Roots and Sources of the Just War Tradition in Western Culture." In Just War and Jihad: Historical and Theoretical Perspectives on War and Peace in Western and Islamic Traditions, edited by John Kelsay and James Turner Johnson, 3-30. Westport: Greenwood Press, 1991.

———. The Holy War Idea in Western and Islamic Traditions. University Park: Pennsylvania State University, 1997.

Libertini, Christopher G. "Practical Crusading: The Transformation of Crusading Practice 1095-1221." In Autour de la Premiere Croisade: Actes du Colloque de la Society for the Study of the Crusades and the Latin East, edited by Society for the Study of the Crusades and the Latin East, 281-291. Paris: Publications de la Sorbonne, 1996.

Menache, Sophia. "The Communication Challenge of the Early Crusades." In Autour de la Premiere Croisade: Actes du Colloque de la Society for the Study of the Crusades and the Latin East, edited by Society for the Study of the Crusades and the Latin East, 293-314. Paris: Publications de la Sorbonne, 1996.

Munro, Dana Carleton. "The Speech of Pope Urban II at Clermont, 1095." American Historical Review 11, no. 2 (January 1906): 231-242.

Norton, Claire. "Crusade/Jihad as Propaganda." Review of The Crusades, Christianity and Islam and Saladin: The Sultan and His Times, by Jonathan Riley-Smith and Hannes Mohring. Holy Land Studies 9, no. 1 (2010): 107-115.

Nydell, Margaret K. Understanding Arabs: A Guide for Modern Times. 4th ed., 107. Boston: Nicholas Brealey Publishing, 2006.

Partner, Peter. God of Battles: Holy Wars of Christianity and Islam, 31-109. Princeton: Princeton University Press, 1998.

———. "Holy War, Crusade and Jihad: An Attempt to Define Some Problems." In Autour de la Premiere Croisade: Actes du Colloque de la Society for the Study of the Crusades and the Latin East, edited by Society for the Study of the Crusades and the Latin East, 333-343. Paris: Piblications de la Sorbonne, 1996.

Riley-Smith, Jonathan. The Crusades: A History. 2nd ed. New Haven: Yale University Press, 2005.

———. "The Motives of the Earliest Crusaders and the Settlement of Latin Palestine, 1095-1100." The English Historical Review 98, no. 389 (October 1983): 721-736. JSTOR.

Robinson, Ian S. Authority and Resistance in the Investiture Contest: The Polemical Literature of the Late Eleventh Century. Manchester: Manchester University Press, 1978.

Saint Augustine. The City of God. Translated by Marcus Dods. New York: The Modern Library, 1950.

Silverman, Adam L. "Just War, Jihad, and Terrorism: A Comparison of Western and Islamic Norms for the Use of Political Violence." Journal of Church and State 44, no. Winter (2002): 73-92.

Talmon-Heller, Daniella. "Islamic Preaching in Syria During the Counter-Crusade (Twelfth-Thirteenth Centuries)." In In Laudem Hierosolymitani: Studies in Crusades and Medieval Culture in Honour of Benjamin Z. Kedar, by Iris Shagrir, Roni Ellenblum, Jonathon Simon Christopher Riley-Smith, and B.Z. Kedar, 61-75. Crusades - Subsidia 1. Burlington: Aldershot England, 2007.

Waterson, James. Sacred Swords: Jihad in the Holy Land 1097-1291. London: Frontline Books, 2010.

Watt, W. Montgomery. "Islamic Conceptions of the Holy War." In The Holy War, edited by Thomas Patrick Murphy, 141-156. N.p.: Ohio State University Press, 1976.

Last Updated: 12/4/14