Answer:
Knights Hospitaller and Knights Templar, both military orders of professional warrior-monks who would make themselves indispensable to the defense of the Crusader States in the Middle East. The lure, although later reduced by Spanish nobles, eventually worked, and both orders would commit knights to the Reconquista. In addition, the Iberian peninsula would see the formation of its own local military orders... A great deal more warriors would soon be on their way to help the Christian Spanish rulers, too, as the riches on offer in southern Spain attracted adventurers.