Quiz: Remember the definition of mal de mer?
1706, respelling of croisade (1570s), from Middle French croisade (16c.), Spanish cruzada, both from Medieval Latin cruciata, past participle of cruciare "to mark with a cross," from Latin crux (genitive crucis) "cross." Other Middle English forms were croiserie, creiserie. Figurative sense of "campaign against a public evil" is from 1786.
1732, from crusade (n.). Related: Crusaded; crusading.
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.