feudum

Feudum is a term from medieval Latin used to designate a fief, a form of feudal land tenure. A feudum referred to property—most commonly land, but sometimes other rights or revenues—granted by a lord to a vassal in exchange for service and allegiance. The grant established a feudal relationship: the vassal owed homage, fealty, and certain duties, often including military service and financial payments; the lord in turn provided protection, jus disponendi (right to use), and sometimes judicial authority over the estate. The term also covers the notion that the feudum could be hereditary, passing to the vassal's heirs, though this often required continued service or reaffirmation to the lord. Subinfeudation was common: a vassal could grant a portion of his feudum to a subordinate, creating a hierarchy of vassals and overlords.

In legal and historical texts, feudum is contrasted with other forms of tenure, such as the beneficium (a benefice without land in some contexts) or possession without feudal duties. The concept is central to the study of feudalism, illustrating how land and power were interconnected through loyalty and service. In modern historical writing, feudum is usually translated as 'fief' or described as a feudal holding; the term is primarily of historical usage rather than a term in contemporary law.