What Were the Crusades?

Overview of Causes, History, and Violence of the Crusades

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Mention the word "crusade" to anyone, and you'll engender visions of either wild-eyed religious fanatics charging off to kill the infidels, or esteemed holy warriors taking up the burden of a religious mission far greater than themselves. There's no single judgment that can be made about the Crusades or even crusading generally, but it is a subject which merits closer attention than it usually receives.

What is a Crusade?

The term "Crusade" can generally be used to refer to any of the military operations launched during the middle ages by the Catholic Church and Catholic political leaders against non-Catholic powers or heretical movements. Most Crusades, however, were directed at Muslim states in the Middle East, with the first starting in 1096 and the last in 1270. The term itself is derived from the Latin cruciata, which means "cross-marked," i.e. cruce signati, those who wear the insignia of scarlet crosses.

Today the term "crusade" has lost its military implications (in the West, at least) and has acquired more metaphorical meanings. Within religion, the label "crusade" may be applied to any organized drive to convert people to a particular brand of Christianity or just to stoke the fires of devotion and faith. Outside of religion, the label is applied to reform movements or zealous undertakings designed to make significant changes in structures of power, authority, or social relationships.

Understanding the Crusades requires understanding that, contrary to traditional stereotypes, they weren't simply an aggressive military campaign against Muslim lands, nor were they merely a defensive military campaign against Muslims on the Iberian peninsula and in the Mediterranean. The Crusades, all of them, were in the first place an attempt to impose Orthodox Christianity via military force across a wide swath of territory, and second, the product of Christian contact with a militarily powerful, culturally self-confident, and economically expansionistic religious civilization.

The Crusades, but especially the "true" Crusades launched against Islam in the Middle East, are arguably the most important aspect of the Middle Ages. It was here that medieval warfare, art, politics, trade, religion, and ideas about chivalry all came together. Europe entered the crusading age as one type of society but left it transformed in vital ways which were not always immediately obvious, but which nevertheless contained the seeds of change which continue to impact European and world affairs today.

Furthermore, the Crusades also fundamentally altered the relationship between Christianity and Islam. Although they constituted a decisive military "win" for Islam, the image of barbaric Christian Crusaders continues to haunt Arab Muslim perspectives of Europe and Christianity, especially when combined with the more recent history of European colonialism in the Middle East. It is curious that an ostensibly Islamic military and political triumph could be transformed into a touchstone of Islamic defeat and despair.

There is some arbitrariness to any categorization or division of the Crusades — over 200 years of almost continual fighting on multiple fronts. Where does one Crusade end and the next begin? Despite such problems, there is a traditional system that allows for a fair overview.

First Crusade

Launched by Pope Urban II at the Council of Clermont in 1095, it was the most successful. Urban gave a dramatic speech urging Christians to swarm to Jerusalem and make it safe for Christian pilgrims by taking it away from Muslims. The armies of the First Crusade left in 1096 and captured Jerusalem in 1099. Crusaders carved out small kingdoms for themselves which endured for some time, though not long enough to have a real impact on local culture.

Second Crusade

Launched in response to the Muslim capture of Edessa in 1144, it was accepted by European leaders primarily due to the tireless effort of St. Bernard of Clairvaux who traveled across France, Germany, and Italy to exhort people to take up the cross and reassert Christian domination in the Holy Land. The kings of France and Germany answered the call but the losses to their armies were devastating, and they were easily defeated.

Third Crusade

Launched in 1189, it was called because of the Muslim recapture of Jerusalem in 1187 and the defeat of Palestinian Knights at Hittin. It was unsuccessful. Frederick I Barbarossa of Germany drowned before he even reached the Holy Land and Philip II Augustus of France returned home after a short time. Only Richard, the Lionheart of England, stayed long. He helped capture Acre and some smaller ports, only leaving after he concluded a peace treaty with Saladin.

Fourth Crusade

Launched in 1202, it was in part instigated by Venetian leaders who saw it as a means to increase their power and influence. Crusaders who arrived in Venice expecting to be taken to Egypt were instead diverted towards their allies in Constantinople. The great city was mercilessly sacked in 1204 (during Easter week, yet), leading to greater enmity between Eastern and Western Christians.

Fifth Crusade

Called in 1217, only Leopold VI of Austria and Andrew II of Hungary participated. They captured the city of Damietta, but after their devastating loss at the Battle of Al-Mansura, they were forced to return it. Ironically, before their defeat, they were offered control of Jerusalem and other Christian sites in Palestine in exchange for the return of Damietta, but Cardinal Pelagius refused and turned a potential victory into a stunning defeat.

Sixth Crusade

Launched in 1228, it achieved some small measure of success — though not by military might. It was led by Holy Roman Emperor Frederick II of Hohenstaufen, King of Jerusalem through his marriage to Yolanda, daughter of John of Brienne. Frederick had promised to participate in the Fifth Crusade but failed to do so. Thus he was under a great deal of pressure to do something substantive this time. This Crusade ended with a peace treaty granting Christians control of several important holy sites, including Jerusalem.

Seventh and Eighth Crusades

Led by King Louis IX of France, they were complete failures. In the Seventh, Crusade Louis sailed to Egypt in 1248 and recaptured Damietta, but after he and his army had been routed, he had to return it as well as a massive ransom just to get free. In 1270 he set off on the Eighth Crusade, landing in North Africa to convert the sultan of Tunis to Christianity but died before he got far. Timeline

The Ninth Crusade

Led by King Edward I of England in 1271 who tried to join Louis in Tunis, it would fail. Edward arrived after Louis had died and moved against the Mamluk sultan Baibers. He didn't achieve much, though, and returned home to England after he learned that his father Henry III had died. Timeline


Launched against the Muslims who had taken control of the Iberian peninsula, it began in 722 with the Battle of Covadonga when the Visigoth noble Pelayo defeated a Muslim Army at Alcama and didn't end until 1492 when Ferdinand of Aragon and Isabella of Castile conquered Granada, last Muslim stronghold.

Baltic Crusade

Launched in the north by Berthold, Bishop of Buxtehude (Uexküll), against local pagans. Fighting lasted until 1410 when at the Battle of Tannenberg forces from Poland and Lithuania defeated the Teutonic Knights. Over the course of the conflicts, though, the pagan population was gradually converted to Christianity.

Cathar Crusade

Launched against the Cathars (Albigenses) in southern France by Pope lnnocent III, it was the only major Crusade against other Christians. Montsegur, the largest Cathar stronghold, fell in 1244 after a nine-month siege and the last Cathar stronghold — an isolated fort at Quéribus — was captured in 1255.

Causes of the Crusades

Why were the Crusades launched? Were the Crusades primarily religious, political, economic, or a combination? There is a wide variety of opinion on this matter. Some argue that they were a necessary response by Christendom to the oppression of pilgrims in Muslim-controlled Jerusalem. Others claim that it was political imperialism masked by religious piety. Still, others argue that it was a social release for a society that was becoming overburdened by landless nobles.

Christians commonly try to defend the Crusades as political or at least as politics being masked by religion, but in reality, sincere religious devotion — both Muslim and Christian — played a primary role on both sides. It's little wonder that the Crusades are so often cited as a reason to regard religion as a cause of violence in human history. The most immediate cause for the Crusades is also the most obvious: Muslim incursions into previously Christian lands. On multiple fronts, Muslims were invading Christian lands to convert the inhabitants and assume control in the name of Islam.​

A "Crusade" had been underway on the Iberian peninsula since 711 when Muslim invaders conquered most of the region. Better known as the Reconquista, it lasted until the tiny kingdom of Grenada was reconquered in 1492. In the East, Muslim attacks on land controlled by the Byzantine Empire had been going on for a long time. After the battle of Manzikert in 1071, much of Asia Minor fell to the Seljuk Turks, and it was unlikely that this last outpost of the Roman Empire would be able to survive further concentrated assaults. It wasn't long before the Byzantine Christians asked for help from Christians in Europe, and it's no surprise that their plea was answered.

A military expedition against the Turks held out a lot of promise, not least of which was the possible reunification of the Eastern and Western churches, should the West prove capable of defeating the Muslim menace which had for so long plagued the East. Thus the Christian interest in the Crusades was not only to end the Muslim threat, but also to end the Christian schism. Aside from that, however, was the fact that if Constantinople fell then all of Europe would be open to invasion, a prospect that weighed heavily on the minds of European Christians.

Another cause for the Crusades was the increase in problems experienced by Christian pilgrims in the region. Pilgrimages were very important to European Christians for religious, social, and political reasons. Anyone who successfully made the long and arduous journey to Jerusalem not only demonstrated their religious devotion but also became beneficiaries of significant religious benefits. A pilgrimage wiped clean one's plate of sins (sometimes it was a requirement, the sins were so egregious) and in some cases served to minimize future sins as well. Without these religious pilgrimages, Christians would have had a harder time justifying claims to ownership and authority over the region.

The religious enthusiasm of the people who went off on the Crusades can't be ignored. Although there were a number of distinct campaigns launched, a general "crusading spirit" swept across much of Europe for a long time. Some Crusaders claimed to experience visions of God ordering them to the Holy Land. These usually ended in failure because the visionary was typically a person without any political or military experience. Joining a Crusade was not simply a matter of participating in military conquest: it was a form of religious devotion, particularly among those seeking ​forgiveness for their sins. Humble pilgrimages had been replaced by armed pilgrimages as church authorities used the Crusades as part of the penance people had to do to repay sins.

Not all of the causes were quite so religious, though. We know that the Italian merchant states, already powerful and influential, wished to expand their trade in the Mediterranean. This was being blocked by Muslim control of many strategic seaports, so if Muslim domination of the eastern Mediterranean could be ended or at least significantly weakened, then cities like Venice, Genoa, and Pisa had a chance to enrich themselves further. Of course, richer Italian states also meant a richer Vatican.

A Violent Time

In the end, the violence, death, destruction, and continuing bad blood that lasts through to the present day would not have occurred without religion. It doesn't matter so much who "started it," Christians or Muslims. What matters is that Christians and Muslims eagerly participated in mass murder and destruction, mostly for the sake of religious beliefs, religious conquest, and religious supremacism. The Crusades exemplify the way in which religious devotion can become a violent act in a grand, cosmic drama of good vs. evil — an attitude which persists through today in the form of religious extremists and terrorists.

The Crusades were an incredibly violent undertaking, even by medieval standards. The Crusades have often been remembered in a romantic fashion, but perhaps nothing has deserved it less. Hardly a noble quest in foreign lands, the Crusades represented the worst in religion generally and in Christianity specifically.

Two systems which emerged in the church deserve special mention has having contributed greatly: penance and indulgences. Penance was a type of worldly punishment, and a common form was a pilgrimage to the Holy Lands. Pilgrims resented the fact that sites holy to Christianity were not controlled by Christians, and they were easily whipped into a state of agitation and hatred towards Muslims.

Later on, crusading itself was regarded as a holy pilgrimage — thus, people paid penance for their sins by going off and slaughtering adherents of another religion. Indulgences, or waivers of temporal punishment, were granted by the church to anyone who contributed monetarily to the bloody campaigns.

Early on, crusades were more likely to be unorganized mass movements of "the people" than organized movements of traditional armies. More than that, the leaders seemed to be chosen based on just how incredible their claims were. Tens of thousands of peasants followed Peter the Hermit who displayed a letter he claimed was written by God and delivered to him personally by Jesus. This letter was supposed to be his credentials as a Christian leader, and perhaps he was indeed qualified — in more ways than one.

Horrors of War

Not to be outdone, throngs of crusaders in the Rhine Valley followed a goose believed to be enchanted by God to be their guide. I'm not sure that they got very far, although they did manage to join other armies following Emich of Leisingen who asserted that a cross miraculously appeared on his chest, certifying him for leadership. Showing a level of rationality consistent with their choice of leaders, Emich's followers decided that before they traveled across Europe to kill God's enemies, it would be a good idea to eliminate the infidels in their midst. Thus suitably motivated, they proceeded to massacre the Jews in German cities like Mainz and Worms. Thousands of defenseless men, women, and children were chopped, burned or otherwise slaughtered.

This sort of action was not an isolated event — indeed, it was repeated throughout Europe by all sorts of crusading hordes. Lucky Jews were given a last-minute chance to convert to Christianity in accord with Augustine's doctrines. Even other Christians were not safe from the Christian crusaders. As they roamed the countryside, they spared no effort in pillaging towns and farms for food. When Peter the Hermit's army entered Yugoslavia, 4,000 Christian residents of the city of Zemun were massacred before they moved on to burn Belgrade.

Eventually, the mass killings by amateur crusaders were taken over by professional soldiers — not so that fewer innocents would be killed, but so that they would be killed in a more orderly fashion. This time, ordained bishops followed along to bless the atrocities and make sure that they had official church approval. Leaders like Peter the Hermit and the Rhine Goose were rejected by the Church not for their actions, but for their reluctance to follow church procedures.

Taking the heads of slain enemies and impaling them upon pikes appears to have been a favorite pastime among Crusaders. Chronicles record a story of a crusader-bishop who referred to the impaled heads of slain Muslims as a joyful spectacle for the people of God. When Muslim cities were captured by Christian crusaders, it was a standard operating procedure for all inhabitants, no matter what their age, to be summarily killed. It is not an exaggeration to say that the streets ran red with blood as Christians reveled in church-sanctioned horrors. Jews who took refuge in their synagogues would be burned alive, not unlike the treatment they received in Europe.

In his reports about the conquest of Jerusalem, Chronicler Raymond of Aguilers wrote that "It was a just and marvelous judgment of God, that this place [the temple of Solomon] should be filled with the blood of the unbelievers." St. Bernard announced before the Second Crusade that "The Christian glories in the death of a pagan because thereby Christ himself is glorified."

Sometimes, atrocities were excused as actually being merciful. When a crusader army broke out of Antioch and sent the besieging army into the flight, the Christians found that the abandoned Muslim camp was filled with the wives of the enemy soldiers. Chronicler Fulcher of Chartres happily recorded for posterity that "...the Franks did nothing evil to them [the women] except pierce their bellies with their lances."