Origin of the phrase "Deus Vult" .

Deus vult (God wills it) was the cry of the people at the declaration of the First Crusade by Pope Urban II at the Council of Clermont in 1095. On November 27, 1095, Pope Urban II made perhaps the most influential speech of the Middle Ages, giving rise to the Crusades by calling all Christians in Europe to war against Muslims in order to reclaim the Holy Land, with a cry of "Deus volt!" or "God wills it!"

By the end of the 11th century, the Holy Land--the area now commonly referred to as the Middle East--had become a point of conflict for European Christians. Since the 6th century, Christians frequently made pilgrimages to the birthplace of their religion, but when the Seljuk Turks took control of Jerusalem, Christians were barred from the Holy City. When the Turks then threatened to invade the Byzantine Empire and take Constantinople, Byzantine Emperor Alexius I made a special appeal to Urban for help. This was not the first appeal of its kind, but it came at an important time for Urban. Wanting to reinforce the power of the papacy, Pope Urban II seized the opportunity to unite Christian Europe under him as he fought to take back the Holy Land from the Turks.

At the Council of Clermont, in France, at which several hundred clerics and noblemen gathered, Pope Urban II delivered a rousing speech summoning rich and poor alike to stop their in-fighting and embark on a righteous war to help their fellow Christians in the East and take back Jerusalem. Urban denigrated the Muslims, exaggerating stories of their anti-Christian acts, and promised absolution and remission of sins for all who died in the service of Christ.

Pope Urban II 's war cry caught fire, mobilizing clerics to drum up support throughout Europe for the crusade against the Muslims. All told, between 60,000 and 100,000 people responded to Urban's call to march on Jerusalem. Not all who responded did so out of piety: European nobles were tempted by the prospect of increased land holdings and riches to be gained from the conquest. These nobles were responsible for the death of a great many innocents both on the way to and in the Holy Land, absorbing the riches and estates of those they conveniently deemed opponents to their cause. Adding to the death toll was the inexperience and lack of discipline of the Christian peasants against the trained, professional armies of the Muslims. As a result, the Christians were initially beaten back, and only through sheer force of numbers were they eventually able to triumph.