The best example is the First Crusade. Eager to unite warring Christians, Pope Urban II spoke in 1095 to a massive crowd in France. Describing the cruelties inflicted by Muslims on Christian pilgrims trying to visit Jerusalem, he called on all of western Christendom to rescue their eastern breth-ren. "They should leave off slaying each other and fight instead a righteous war, doing the work of God, and God would lead them...." Runciman writes. "Here they were poor and unhappy; there they would be joyful and prosperous and true friends of God."
The response was tremendous. Urban's speech was interrupted by cries of "Deus lo volt"—"God wills it." Hundreds begged to go on the holy expedition. Soon tens of thousands of commoners and knights were heading off to the Holy Land. Across Europe, preachers called on the faithful to sew crosses on their clothes, to mark them until they succeeded in their quest.
The key to Urban's call was a revolutionary (and doomed) theology: salvation through the sword. "There is a very powerful devotional element," says Riley-Smith. "West European Catholics believed they could aid their salvation by fighting the infidel in the East. [Crusading is] as much a penance as fasting on bread and water.... This idea is without precedent in Christian history."
Jerusalem was the medieval Christians' equivalent of Mecca, Christ's tomb their quest. To take up the cross in the city's defense was a deeply spiritual act for many. Superstitious peasants saw the journey as a road to heaven. Fiery itinerant preachers like Peter the Hermit, whose army of starving peasants had no place in Urban's vision of an orderly march on Jerusalem, promised paradise. "Many...believed that he was promising to lead them out of their present miseries to the land flowing with milk and honey of which the Scriptures spoke," Runciman writes.
Peter's success was cited repeatedly. The defeats suffered by better-organized Crusades led many to believe that it was the humble who were destined to succeed, not the proud, rich military classes. In the end, these "People's Crusades" ended in disaster, too. None ever reached the Holy Land, and most of the peasant Crusaders were either slaughtered as they plundered their way across Europe or disbanded before ever reaching a port. Without the resources to reach the Holy Land, many turned on more convenient targets, like local Jewish enclaves. "[Why] are we going to seek out our profanity and to take vengeance on the Ishmaelites for our Messiah, when here are the Jews who murdered and crucified him?" was the rationale, as recorded by a Jewish eyewitness.
But persuading landed knights to take up the cross took more than anti-Semitic rants and vague stories of the Promised Land. Europe's warrior class, the fighting force Pope Urban II really wanted, had much to lose: Crusaders faced death, disease, or capture. There were also more-mundane risks. A knight's lands and title could be stolen in his absence. If his Crusade failed, the returning knight risked the scorn of those who blamed him for failing to do God's work. And the costs involved in crusading were a risk in themselves. King Louis IX of France (later to become St. Louis) set out in 1249 on a crusade from a harbor he had specially constructed with an artificial canal and grand tower, stocked with plentiful supplies. He spent six times his annual revenue on the venture, which ended when he was captured and forced to pay a 400,000-pound ransom. "Most Crusaders engaged in a dangerous, unpleasant, unprofitable, and extremely expensive enterprise," says Riley-Smith, "and they do not seem to have expected anything else."
Though most were military and financial fiascoes, the Crusades had a long-term impact on European civilization that went beyond finding an outlet for the violence of warring Christian kingdoms. "[The Crusades] made the Continent more cosmopolitan and gave Europeans a far greater awareness of the wider world. Like all wars, veterans came back and had seen things they never would have if they had stayed in their villages," says James Reston Jr., author of Warriors of God: Richard the Lionheart and Saladin in the Third Crusade. The stories they brought back also sparked a blaze of creativity. Beginning in the 12th century, or around the time of the First Crusade, literature and verse flowered in the form of memoir and song. Coming after the virtual silence that marked the Dark Ages, the proliferation of Crusader epics like the French Song of Roland is called by some scholars the "12th-century Renaissance."