The followers of Christ do not blow up planes, buildings and people and don't go out on a killing spree in villages, theaters, concerts, hotels, shopping malls and concerts. They do not execute journalists or decapitate those who disagree with their believes.http://radioislam.org/sindi/croisades.htm
The most prominent of all the participating fanatics and zealots among the Crusaders, however, was a strange Frenchman by the name of Pierre L'Ermit ("Peter the Hermit") from the city of Amiens. Pierre L'Ermit was one of history's most bizarre characters, especially for a religious leader. He looked like a madman; small and miserably thin; walked barefooted; rode a jackass for transportation; his wild unkempt hair tumbled over his neck and ears; his unshaven wild beard came down to his waist; his eyes rolled; his speech was torrential; and his dingy clothes consisted of only a woolen smock and a light cloak which also served him as a blanket at night.  Pierre L'Ermit was a powerful speaker, though. His fiery speeches hypnotized his Christian listeners who nicknamed him "Kiokio" (or "little Peter"). His followers used his jackass as an object of religious veneration, plucking hairs from its tail to keep as "holy relics"!  It was this strange, barefooted Pierre L'Ermit who led the first column in the First Crusade (known as the Peasants' Crusade) in 1096 against the Arabs and Islam.
In order to raise a large army to fight the Arabs and Islam, Pope Urban II promised that all Crusaders would be exempted from taxes; their debts would be forgiven; their sins would be washed away; and their special place in Paradise would be guaranteed. Consequently, the response to his call was extraordinary. All in all about 160,000,  heavily armed Europeans, an astounding figure for that time, formed the armies of the First Crusade. It seemed that the whole of Western Europe was marching east. It was the first time that Western Europe had come together for any cooperative act or cause since the fall of the Roman Empire. Nothing like it has ever happened in the history of the West. European unity was so clear and so purposeful.
The Crusaders came in a seemingly solid mass, some with all of their belongings, to join in this mad holy war to destroy Islam. Their objective was to kill Arabs and Turks whom Pope Urban II described as "an accursed race, a race utterly alienated from God", urging his followers to "exterminate this vile race from our lands."  The Crusades took place during the Western dark ages when Europe was backward compared to the Arab/Muslim world and to the Christian Byzantine Empire of East Europe. Hence, the Crusaders' behavior during their vicious wars reflected their cruelty and primitive barbarism. They were extremely militant, and committed incredible mass violence. They acted like modern-day violent American Ku Klux Klan and other Western racist groups. They committed, both in Europe and the Arab/Muslim world, the worst conceivable horrible crimes and atrocities, not only against thousands of innocent Muslims and Jews of both sexes and of all ages, but also even against Christians. Their vicious crimes - all of which will be detailed shortly - against noncombatants and innocent peoples included the destruction of properties; pillaging; plundering; foraging; ravaging; stealing; setting houses on fire; torturing; murdering; executing; burning humans alive; raping women, including nuns; and even roasting and eating (with a great deal of relish) the human flesh of their victims and their children.