|1.||(often capital) any of the military expeditions undertaken in the 11th, 12th, and 13th centuries by the Christian powers of Europe to recapture the Holy Land from the Muslims|
|2.||(formerly) any holy war undertaken on behalf of a religious cause|
|3.||a vigorous and dedicated action or movement in favour of a cause|
|4.||to campaign vigorously for something|
|5.||to go on a crusade|
|[C16: from earlier croisade, from Old French crois cross, from Latin crux; influenced also by Spanish cruzada, from cruzar to take up the cross]|
A series of wars fought from the late eleventh through the thirteenth centuries, in which European kings and warriors set out to gain control of the lands in which Jesus lived, known as the Holy Land. At that time, these areas were held by Muslims. The Crusaders conquered Jerusalem in 1099 but failed to secure the Holy Land, and they were driven out by the late thirteenth century. Nevertheless, the Crusades had several lasting results, including the exposure of Europeans to the goods, technology, and customs of Asia.
Note: The Crusades left a legacy of bitterness against Europeans and Christians among Muslims.