Definition
An agillarius was an officer of medieval English agricultural communities responsible for keeping and tending the herd of cattle pastured on common fields. The term is Latin-derived and appears in old English legal records to denote a hayward or herdward — a person charged with the practical management of communal livestock and, in some usages, the supervision of hedges, enclosures, and crops to prevent damage by straying animals. The role was a recognized legal and customary office within the manorial system, carrying defined duties and, in some communities, corresponding liability for losses caused by neglect.
Why It Matters in Research
Agillarius is a term researchers will encounter almost exclusively in medieval English legal records, manorial rolls, and early treatises on common-field agriculture. It does not survive into modern legal usage and carries no active doctrinal significance today. Its research value is historical and contextual: understanding the term clarifies the structure of manorial administration and the legal duties attached to communal land use in pre-enclosure England.
Researchers working in medieval manor court records, copyhold tenure materials, or the early history of agricultural commons should note that the agillarius occupied a position closely related to — but distinct from — other manorial officers such as the reeve and the pinder. Conflating these offices distorts the picture of how responsibility for livestock and crop damage was allocated within a manor. Sources from different regions and periods may use agillarius, hayward, and herdward interchangeably or with subtle distinctions; cross-referencing the Latin and English terminology in a given document corpus is advisable before drawing conclusions about the precise duties described.
The term is also relevant to the history of communal grazing rights, common of pasture, and the legal consequences of damage done by animals to crops — a line of liability running forward into later English common law even after the agillarius as a formal office disappeared with enclosure.
Historical Dictionary Support
The historical dictionaries are in close agreement on the core meaning. Black's Law Dictionary (both first and second editions) and Burrill's Law Dictionary each define agillarius as a hayward, herdward, or keeper of the herd of cattle in a common field, with Burrill and Black's second edition each citing Cowell's legal glossary as authority. Rapalje and Lawrence offer a slightly condensed formulation — "a keeper of cattle in a common field" — without the hayward/herdward elaboration, but do not contradict the other sources.
None of the historical dictionaries provide substantial detail about the legal duties, liability, or procedural standing of the agillarius within manorial proceedings. For that level of detail, researchers must consult primary manorial sources and specialized treatments of medieval agrarian law. Cowell's Interpreter, cited by Burrill and Black's, remains the closest historical legal reference point for the term's definition.