The Origins of the Crusades

The origins of the Crusades in general and the First Crusade in particular have been widely debated by scholars and historians.

Europe Before the Crusades

Early in the Middle Ages, after the decline of the Western Roman Empire, Christianity had spread through much of Europe and the Middle East. However, from the 8th Century on, the spread of Christianity was slowed by the rise of Islam under the rule of the Umayyad Caliphate and eventually spread from what is now Saudi Arabia on the Arabian Peninsula to Spain and parts of France.

Meanwhile, in Western Europe, the Spanish Reconquista was already underway. While the Reconquista did have an ideological component, it cannot be considered a crusade or a holy war.

In Eastern Europe, the Christians had been in schism with the west since 1054. It is believed that the Crusades were seen as a way to strengthen the power of the Catholic Church in the region by helping to prop up the Byzantine Empire. This is felt by some historians to be a possible catalyst for the First Crusade because the Byzantines were at war with the Seljuk Turks of the Ottoman Empire over Anatolia and the Levant. It is believed that the Byzantines saw themselves as being surrounded by enemies, the Turks on one side and the Normans on the other.

Western Europe had only recently begun to stabilize after the Christianization of the Saxons, Vikings and Magyars. However, this led to another problem. There were now large numbers of professional warriors with nothing to do, but fight amongst themselves. As a result, both for a way to keep the peace in Europe and for reasons of political expedience, Popes began to look for ways to utilize these soldiers in the name of Christendom.

The Historiography of the Crusades

According to the Erdman Theory, which was developed by German historian Carl Erdman, the origins of the Crusades can be directly linked to Papal reform movements, such as the one described above. The Erdman Theory states that the real purpose of the Crusades was to prop up the crumbling Byzantine Empire, which was slowly losing territory to the Ottoman Empire.

This suggests that the principle goal of the Crusades was to protect the eastern borders of the Christian world. The liberation of Jerusalem was a secondary priority.

More recently, historians have begun to examine the role that the rise of Islam played in the events leading up to the beginning of the Crusades. The idea of the Crusades as a response to the expansion of Islam goes back the 12th Century when William of Tyre began his chronicle of the Siege of Jerusalem by recounting the first Arab invasions several centuries early, as well as the destruction of the Church of the Holy Sepulchre in Bethlehem in 1009 and the attacks on German pilgrims in the Great German Pilgrimage in 1065.

These were recent events that Pope Urban II would use to stir up piety and support among lay Christians at the Council of Clermont in 1095.

Works CitedD. Nicolle, The First Crusade 1096–99: Conquest of the Holy Land, 21


D. Nicolle, The First Crusade 1096–99: Conquest of the Holy Land, 32

Peter M. Holt, The Age of the Crusades: The Near East from the Eleventh Century to 1517 (Longman, 1986), pp. 11, 14–15

The First Crusade and the Idea of Crusading (University of Pennsylvania Press, 1986), pp. 5–8


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