The siege of Acre took place in 1291 and resulted in the Crusaders' losing control of Acre to the Mamluks. It is considered one of the most important battles of the period. Although the crusading movement continued for several more centuries, the capture of the city marked the end of further crusades to the Levant. When Acre fell, the Crusaders lost their last major stronghold of the Crusader Kingdom of Jerusalem. They still maintained a fortress at the northern city of Tartus, engaged in some coastal raids, and attempted an incursion from the tiny island of Ruad; but, when they lost that, too, in a siege in 1302, the Crusaders no longer controlled any part of the Holy Land.

The Crusades were a series of religious wars initiated, supported, and sometimes directed by the Christian Latin Church in the medieval period. The best known of these military expeditions are those to the Holy Land in the period between 1095 and 1291 that had the objective of reconquering Jerusalem and its surrounding area from Muslim rule after the region had been conquered by the Rashidun Caliphate centuries earlier. Beginning with the First Crusade, which resulted in the conquest of Jerusalem in 1099, dozens of military campaigns were organised, providing a focal point of European history for centuries. Crusading declined rapidly after the 15th century.