Let's start by saying that initially the Crusades were not a holy war on the part of Europeans against Islam, but in important ways, the Crusades were driven by religious faith. Mr. Green, Mr. Green, religion causes all wars. Imagine no religion. I'm going to cut you off right there before you violate copyright me from the past, but as usual, you're wrong. Simple readings of history are rarely sufficient. By the way, when did my handwriting get so much better? I mean, if the Crusades had been brought on by the lightning-fast rise of the Islamic Empire and a desire to keep in Christian hands the land of Jesus, then they would have started in the 8th century.