Definition
Latin term for parliament. In medieval and early modern English legal usage, parliamentum denoted the supreme council and highest legislative assembly of the realm of England, functioning simultaneously as a legislative body and the highest court of the realm. The term appears in foundational English legal texts to describe the institution that would evolve into the Parliament of England, later Great Britain, and ultimately the United Kingdom.
Two named historical forms deserve specific attention:
1. Parliamentum Diabolicum ("Devil's Parliament"): The parliament held at Coventry in the 38th year of Henry VI's reign, at which Edward, Earl of March (later King Edward IV) and many of the chief nobility were attainted. The acts passed at this parliament were subsequently annulled by the succeeding parliament. The name reflects the hostility of later commentators to the proceedings.
2. Parliamentum Indoctum ("Unlearned Parliament" or "Lack-Learning Parliament"): A parliament to which lawyers were excluded from election as members — so called because it sat without the professional legal knowledge that lawyer-members would ordinarily supply.
Common Confusion
Parliamentum should not be conflated with the modern institution of Parliament. The Latin term, as it appears in historical legal sources, encompasses a broader and older conception: parliamentum was simultaneously a court, a counsel to the Crown, and a legislative body. The modern Parliament retains only the legislative character in ordinary understanding. Researchers encountering parliamentum in Year Books, early treatises, or monastic charters are reading about an institution structurally and functionally distinct from its modern descendant.
Why It Matters in Research
The primary research significance of this term is navigational and interpretive. Parliamentum appears in Latin in Bracton, Fleta, Coke's Institutes, and other foundational texts of the common law. When encountered in those sources, it carries the full freight of the medieval conception — a court of record, a supreme tribunal, and a deliberative assembly all at once — not merely a legislature.
Several traps await researchers working in historical sources:
Age of sources: Burrill cites a charter of Ceolwulf, King of the Mercians, dated A.D. 872, as an early occurrence of the word. This pushes the term's documented use back to the Anglo-Saxon period, long before Parliament as an institution took recognizable form. Encountering parliamentum in a document of that era means something closer to a royal council or general assembly than anything resembling parliamentary procedure.
Jurisdictional layering: English legal history exported the concept — and the Latin label — to Ireland and, in modified forms, to colonial legislatures. Researchers in those corpora will encounter parliamentum as a reference point even when the local institution bore a different name or character.
Named variants: The Parliamentum Diabolicum and Parliamentum Indoctum are recognized historical terms of art. They appear in secondary literature and occasionally in primary sources. Knowing their identity prevents misreading a charged label as merely descriptive language.
Court function: Because the medieval parliamentum was the highest court of the realm, it will appear in discussions of appellate jurisdiction and judicial history in ways that seem anomalous to a researcher expecting a purely legislative body. This court character explains, for example, why impeachment proceedings and bills of attainder were historically parliamentary acts.
Historical Dictionary Support
Burrill and Black's agree on the core definition — Latin for the English Parliament, understood as both supreme legislative assembly and highest court — but Burrill is considerably richer in primary citations, pointing to Coke's Littleton (109b), the Fourth Institute (c. 2), Fortescue's De Laudibus Legum Angliae (c. 18), and Fleta (lib. 2, cc. 2 and 64). These citations anchor parliamentum firmly in the classical common law treatise tradition and give researchers precise entry points into those texts.
Black's adds the named subtypes — Parliamentum Diabolicum and Parliamentum Indoctum — with brief but useful identifications, crediting Jacob's Law Dictionary for the Diabolicum entry. Neither dictionary substantially addresses the Anglo-Saxon antecedents that Burrill briefly mentions via Spelman, nor do they trace the institutional evolution through which parliamentum gradually shed its judicial character. Researchers looking for that evolution will need to go beyond either dictionary to the historical literature on Parliament's constitutional development.