The political and social system in medieval Europe known as feudalism was characterized by a hierarchical structure of land ownership and obligations. At the top of the system was the monarch, who granted land (fiefs) to nobles (lords) in exchange for military service. These lords would, in turn, grant portions of their land to vassals (lesser nobles or knights) for loyalty and service. Peasants or serfs worked the land and provided agricultural products, while also owing labor and tribute to their lords. This system created a rigid social structure and influenced economic, military, and political life during the Middle Ages.