Each week, In Theory takes on a big idea in the news and explores it from a range of perspectives. This week we’re talking about just war theory. Need a primer? Catch up here.

Thomas Madden is professor of history and director of the Center for Medieval and Renaissance Studies at Saint Louis University.  

When the Islamic State justified its attacks on Paris as a response to a French “Crusader campaign, the group was taking part in a long-held tradition of the Muslim Middle East, that of viewing relations between Islam and the West through the lens of medieval events.

Indeed, Americans may be surprised to learn that they are routinely tagged as “crusaders” by Islamists. The 9/11 attacks were the result of a fatwa declared by Osama bin Laden “against the Jews and the Crusaders. Since the Islamic State’s goals are themselves medieval — to create a worldwide caliphate — it is unsurprising that the group sees Western motivations in that same light. From its perspective, every contact with the West — whether social, cultural or military — is a crusader’s campaign to destroy Islam and colonize its lands.

The Islamic State’s depiction of the Crusades as colonialist enterprises has a long pedigree, but not a factual one. It is instead a pastiche of 19th and 20th century prejudices and agendas grafted clumsily onto western Europe’s medieval holy wars. Over the past half-century, legions of historians specializing in the study of the Crusades have brought the campaigns into much sharper focus. Hundreds of scholarly monographs and thousands of journal articles, however, have not managed to shift popular misconceptions around the Crusades.

The Crusades were military campaigns, but they could not have happened were they not also devotional exercises. Centuries before the first Crusader took his vow, Muslim armies had waged vigorous jihads against the Christian world. By the year 1000, nearly two-thirds of the old Christian world had been lost to Muslim conquest, including Syria, Palestine, Egypt, all of North Africa, Sicily and much of Spain. Nine years later, Caliph Al-Hakim ordered the complete destruction of the ancient Church of the Holy Sepulchre, the holiest site on earth for Christians, traditionally held to contain the site of Jesus’s crucifixion and his empty tomb.

In 1071, the Seljuk Turks defeated the Christian Byzantine Empire and by 1073 had conquered Jerusalem. The subsequent chaos led to dramatic persecutions of Christian pilgrims. Things became so bad that the Christian emperor in the East, Alexius I Comnenus, turned to the last significant Christian power left in the world — the medieval West.

He asked Pope Urban II to rally the warriors of Europe to turn back the Muslim conquests of Christian lands. At the Council of Clermont, Urban brought that appeal to an assembled body of French knights. Because they would have to undertake the expedition at their own expense and peril, Urban declared the Crusade to be a full penance for the sins of the Crusaders. As professional warriors, they had a great many sins for which to atone. Over the subsequent centuries of Crusades, the overall booty captured was poor and rarely enough to make up the cost of participating. But every Crusader received an abundance of penitential grace, which from a medieval perspective explains why they took on these difficult and dangerous missions.

By the Christian standards of St. Augustine and those of ancient Rome, the Crusades were just wars. They were a response to repeated aggression, had a set goal to repeal the fruits of that aggression and were instituted by a well-established authority. In later decades, theologians and canonists developed precise canon law regarding future Crusades, further underscoring that they could only be called in defense of the Christian people and faith. Crusaders honestly saw themselves as undertaking acts of charity and love for their Christian brothers and sisters in the East.

Of course, that is not how the Islamic State sees the Crusades, nor how many in the West do today. Instead, in the modern caricature, religious piety is replaced with simple colonialism. That is no accident. During the 19th century, European colonial powers wrapped their overseas ventures in an imagined robe of crusading glory.

After the collapse of the Ottoman Empire — the last great Muslim state — the League of Nations gave control of Palestine to Britain and Syria to France. Steeped in a romantic vision of their medieval pasts, these European powers portrayed their entry into the Muslim Middle East as the final chapter in the long history of the Crusades. The popular London magazine, Punch, ran a drawing of Richard the Lionheart staring out over the British entry into Jerusalem with the caption, “At last, my dream comes true.” After taking command in Syria, the French General Henri Gouraud remarked, “Behold, Saladin, we have returned.”

All of this colonial bravado was completely lost on the Muslim inhabitants of the Middle East, most of whom had never heard of the Crusades, which were too insignificant and too foreign to feature in the history of Islam. But that was about to change. In the new colonial schools Europeans taught the Muslim world about the Crusades.

To be more precise, they promulgated a colonialists’ vision of the Crusades, one that emphasized the nobility of the medieval knights as precursors to the age of European imperialism. Islamic history was thus rewritten, obscuring Muslim victories and replacing them with a fable of Western paternalism. The Crusades, recast as Europe’s first colonial venture, became the new pivotal event in Muslim history. It is the one the Islamic State still clings to today.

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