In medieval Europe, land was the most important source of wealth. The lord (feudal lord) granted land to vassals who promised loyalty and service in return. This system of land tenure, called feudalism, formed the basis of medieval society and was widespread in Europe during the Middle Ages. Lords typically granted land to nobles, knights, religious institutions, and wealthy merchants in exchange for military service, political support, or other forms of service. The recipient of the land would become a vassal of the lord and would owe him/her fealty and homage.