crusade

Any one of a series of wars 1095–1291 undertaken by Christian Europeans to take control of Palestine, the Holy Land, from the Muslim rulers of the Middle East. Sanctioned by the pope, leader of the Roman Catholic Church, the aims and effects of the crusades were varied. The crusaders were motivated by religious zeal and a desire for land and wealth, and the trading ambitions of the major Italian cities were also significant. The term came to embrace any war or campaign for alleged religious, political, or social ends.

The first crusaders wanted to ensure the safety of pilgrims visiting the Holy Sepulchre in Jerusalem, and to establish Christian rule in Palestine. They continued for more than 200 years, with hardly a decade passing without one or more expeditions. Later they were extended to include most of the Middle East, and attacks were directed against Egypt and even against Constantinople (Istanbul).