Definition
Latin: "the third penny of the county." A fixed revenue entitlement in Anglo-Saxon and early Norman England by which an earl (comes) received one-third of the fines, forfeitures, and judicial profits arising from the county court within his earldom. The remaining two-thirds were reserved to the Crown. The payment functioned as an official stipend tied to the earl's administrative and judicial role over the county, not as a personal property right in the modern sense.
Why It Matters in Research
This term appears almost exclusively in sources dealing with Anglo-Saxon and early Norman constitutional and administrative history. Researchers encountering it in historical records should understand several navigational points.
First, the term is archaic even within medieval legal literature — by the high medieval period the earldom system had been substantially reorganized, and the denarius tertius comitatus had largely ceased to function as a living institution. References to it in later sources are typically antiquarian or explanatory rather than operative.
Second, the term sits at the intersection of feudal revenue law, county administration, and the history of the earldom as an office. A researcher working on the constitutional status of earls, the development of county courts, or the fiscal relationship between Crown and nobility in pre-Conquest and immediately post-Conquest England will encounter this term as a marker of that larger institutional framework.
Third, because the term appears in Latin and in sources like the Laws of Edward the Confessor and the Liber Niger Scaccarii (Black Book of the Exchequer), researchers relying on translations or abstracts may miss it entirely. The full Latin phrase is the reliable search term; English glosses vary.
Fourth, be alert to the distinction between the denarius tertius comitatus as a formal entitlement attached to the office of earl and informal or irregular arrangements by which individual magnates may have extracted similar revenues outside this framework. Historical sources sometimes conflate the two.
Historical Dictionary Support
Black's and Burrill's are in agreement on the core substance: the denarius tertius comitatus was the third part of county revenues paid to the earl as an official stipend, with two parts reserved to the Crown. Burrill's is the more useful entry for researchers, identifying the specific institutional source of the revenues as fines and profits of the county courts, and pointing toward the comes as an officeholder rather than a mere territorial lord.
Burrill's also supplies documentary anchors — the Laws of Edward the Confessor (c. 31) and the Liber Niger Scaccarii — which provide a starting point for primary source investigation. Cowell's Interpreter is cited as an intermediate authority. Black's entry, by contrast, is compressed to the point of losing the institutional context: describing it simply as "a third part or penny of the county paid to its earl" omits the critical fact that the revenues derived specifically from county court proceedings, not from general county taxation or land revenues.
Neither dictionary addresses the decline of the institution or its relationship to later developments in earldom tenure. Both treat it as a historical curiosity rather than a living doctrine, which accurately reflects its status by the time legal dictionaries were being compiled.
Jurisdictional Note
This term is specific to English legal history and has no application in American, Scottish, or other common law jurisdictions. Researchers working in Welsh, Irish, or Norman French legal contexts from the same period may encounter analogous but distinct revenue-sharing arrangements that should not be conflated with the denarius tertius comitatus.