A fief was a piece of land granted by a lord to a vassal in exchange for loyalty and service during the medieval period. This system was part of the larger structure known as feudalism, where land ownership and social hierarchy were crucial. The vassal would manage the fief, ensuring it was productive and could support both the lord and the vassal's own household. In return for the land, the vassal promised to provide military support and other services to the lord. This relationship created a bond of mutual obligation, where both parties relied on each other for protection and resources. Fiefs could vary in size and value, often including villages, farms, and even castles.