The Crusader Kingdoms were founded in the wake of the First Crusade, so an understanding of the crusades and their genesis is essential to any study of the crusader kingdoms.
Essentially, the Crusades were a series of campaigns undertaken by Christians in the 11th to 13th centuries to establish (or re-establish) control over the Holy Land (the sites of Christ’s passion), particularly Jerusalem. These campaigns were a response to the expansion of Islam, which had spread in the wake of invading armies that used the sword to impose Islam on previously Christian territory. Most – but not all – crusades were fundamentally defensive campaigns that responded to aggression with aggression.
The successful First Crusade established a string of Christian states in the Holy Land that, although prosperous, were always threatened by the overwhelming military superiority of the surrounding Muslim states. Whenever one or more of these states was invaded or fell to the Saracens (the opposing Muslim forces, which were ethnically Egyptian, Syrian, Kurdish or Turkish; I will use the contemporary term “Saracen” to refer to these diverse but consistently Muslim fighting groups), the call went out to the West for aid – for a new crusade. Thus in the course of two centuries, a total of eight numbered crusades were launched, not counting such tragedies as the Children’s Crusades, the Reconquista (liberation) of the Iberian Peninsula, or the wars against the heathens of northeastern Europe and the heretics of Southern France, which were sometimes also referred to as crusades.
In the course of these crusades, Christian leaders and troops committed many atrocities that are incompatible with Christianity, but not all crusaders were inherently depraved and brutal. Furthermore, the enemy also committed countless well-documented atrocities. These were violent centuries, but they were also a period in which the close contact between the East and the West produced cross-fertilization of culture and art, and a period in which trade and science flourished.
Below is a short chronology of the events leading up to the First Crusade:
The First Muslim Invasion of Christian Territory: 632-750
Between 630 and 750, Islam aggressively expanded across North Africa and into the formerly Christian territories of the Byzantine Empire. They captured the Holy Land, including Jerusalem, and also modern-day Syria, Iraq, and Iran. Cyprus and other islands in the Mediterranean were also either conquered or subjected to destructive raids.
The First Muslim Invasion of Western Europe: 710-732
The first Muslim invasion of Western Europe started in 710 with the invasion of the Iberian Peninsula by Muslim armies from North Africa. The Muslim armies conquered the bulk of what is now Spain and Portugal, establishing Muslim states that over the next five centuries developed flourishing cities and a highly sophisticated culture. In 732 a Muslim army crossed the Pyrenees, defeated the Christian forces in what is now Aquitaine, and continued north, approaching the Loire valley. They were stopped and forced to withdraw by Charles Martel, the leader of the Franks, near Poitiers in 732.
Further Muslim Conquests: 827-878
Sicily and Crete were conquered by Muslim forces.
First Christian Offensive: 969-975
The Byzantine Empire made its first attempt to reconquer lost Christian territory in 969, with the recapture of Antioch. By 975 the Byzantine army had captured much of Palestine, particularly on the coast, but the Christian armies failed to capture Jerusalem. A peace treaty in 1001 ended the Byzantine attempt to re-establish political control over the Holy Land and resulted in a period of intensive persecution for native Christians living under Muslim rule. The situation improved somewhat by the middle of the 11th century.
The Norman Conquest of Sicily: 1061-1091
The Norman adventurer Roger de Hauteville recaptured Sicily from the Muslims, who were fighting among themselves, in a series of campaigns between 1061 and 1091. Sicily thereafter fell under the Latin rather than the Byzantine Church, but remained Christian until the present.
The Rise of the Seljuk Turks: 1056-1075
Turkish tribes, who had converted to Islam, began to establish an empire in the 11th century, conquering large parts of Persia and Armenia. In 1071 they destroyed a Byzantine army sent to stop their westward expansion and captured Jerusalem along with the rest of Palestine. The Seljuk Empire soon stretched from Aleppo to Egypt. Christians, whether pilgrims to Jerusalem or merchants, were now more likely to be robbed or enslaved than left in peace.
The Call for a Crusade: 1095
The Byzantine Emperor Alexios Komnenos saw in the internal conflicts between Turks, Syrian Muslims, and Egyptian Muslims the chance to restore Christian rule to the Holy Land, but lacked the military strength to make an attempt. He appealed to the Pope, highlighting alleged atrocities committed against Christians in the Holy Land and other former Byzantine territories. On November 27, 1095, Pope Urban II delivered a rousing speech, calling for Christians to free Jerusalem from the Muslims and reopen it to Christian pilgrims. Urban II was both persuasive and charismatic, and he must have struck a chord with his listeners; it is recorded that the audience spontaneously started chanting “Deus le volt” (God wills it). When he finished speaking, many men crowded around him, vying to be among the first to “take the cross” – that is, to wear a cross on their sleeve as a symbol of their vow to free the Holy Land from Muslim rule. The concept of a crusade – a Christian holy war – had been born. (The notion of jihad – Muslim holy war – was, of course, already hundreds of years old by then.)