knight's fee

In the 150 years after the Norman Conquest, a grant of land by the Crown which was held by a lord on condition that a knight would perform strict duties as required, such as 40 days' military service or castle duty. Though the fee could be the estate of one man, it was usually granted out in multiples, and it is sometimes said that the most common formula was that for every 5 hides of land granted to a lord, one knight was required by the king. Heirs to a knight's fee who were minors became wards of the Crown, which took control of the land, or granted it to another, until they were of age. This feudal system of tenure ended with the Civil War.