The Crusades were a series of religious wars during the Middle Ages between Christian and Muslim armies fighting for control of the Holy Lands, an important area in the Middle East centered around Jerusalem. Pope Urban II launched the First Crusade in 1095 by calling on all Christians to march to the Middle East, capture Jerusalem from Muslim rule, and help defend pilgrims visiting Christian holy sites. Tens of thousands joined the Crusade, which succeeded in taking Jerusalem in 1099 after capturing several other Muslim cities. The Crusades established Christian kingdoms in the region and sparked centuries of ongoing religious conflict, though Jerusalem was eventually recaptured by Muslim leader Saladin in 1187.