The Crusades were a series of wars between Christians and Muslims in the Middle East. It started mainly due to a fight for areas thought to be Holy Land. Both Muslims and Christians considered the same lands holy for reasons like Jesus' resurrections and Muhammad visiting there. The eight big crusade expeditions occurred during 1096 to 1291. The Holy Land is very important for the three major monotheistic religions: Islam, Judaism, and Christianity. There are many important religious sites in the Holy Land. This is the land now called Israel. Jerusalem, Nazareth, Bethlehem and other religious sites fell under the control of Muslims during the Caliphate of Omar.