The feudal system was a hierarchical system of land ownership and social organization that dominated medieval Europe. At the top of the system was the king, who granted land to nobles in exchange for their loyalty and military service. The nobles, in turn, granted land to lesser nobles and knights, who swore fealty to them. At the bottom of the system were peasants, who worked the land in exchange for protection from the nobles. Feudalism was based on the exchange of land for loyalty and military service, with obligations and rights flowing both up and down the social hierarchy.
