Definition
Caput is a Latin term meaning "head," used across several distinct legal contexts in both common law and civil law traditions.
1. Person or legal personality. In its broadest legal sense, caput denotes an individual person — their whole existence as a legal subject, including life, status, and civil condition. In Roman and civil law, caput referred specifically to the bundle of legal attributes that determined one's standing before the law.
2. Civil status (Roman law). Among the Romans, caput comprised three component elements of legal personality: liberty (libertas), citizenship (civitas), and family standing (familia). A diminution or loss of any of these elements was called capitis deminutio — a reduction of one's legal head. Total loss of caput, as in slavery or outlawry, meant the person ceased to exist as a legal subject.
3. Common law senses. At common law, caput carried several more concrete meanings: (a) the head of a county — that is, the sheriff, or the king as ultimate sovereign; (b) a person or a life, in the sense of a countable legal unit; (c) the upper part of a town; and (d) a castle, particularly as the principal seat or strongpoint of a lordship.
4. Estimatio capitis. Anderson's Dictionary of Law highlights a related phrase: estimatio capitis, the "value of a head" — the prescribed monetary sum owed for unlawfully taking another person's life. In Saxon law this was a fixed wergild-type payment; in modern law the concept maps roughly onto wrongful death damages.
Common Language
Modern common usage (Wiktionary): The head; a knob-like protuberance; the top or superior part of a thing; the governing council of Cambridge University prior to 1856; also used medically (caput succedaneum).
Historical common usage (Webster's 1913): The head; the top or superior part of a thing; the ruling body of Cambridge University. Also caput mortuum — the worthless residue remaining after distillation, used figuratively for a person of no value or substance.
The common English senses of caput are purely anatomical or positional — "the top of a thing." The legal senses are entirely different: caput in law is about personhood, status, and legal capacity. A reader encountering caput in a legal text and reaching for the anatomical meaning will badly misread what is at stake. The Cambridge University sense (a governing council) is a curio that occasionally appears in English legal and institutional history but is unrelated to either the civil law or common law meanings.
Common Confusion
Caput and per capita are closely linked but distinct. Caput is the unit — a single legal person. Per capita ("by heads") is the distributional principle built on it: dividing an estate or benefit equally among individuals rather than by family branch (per stirpes). Researchers working with inheritance and intestacy materials should take care to distinguish references to caput as a concept of legal personality from its use as the arithmetic unit underlying per capita distribution rules.
Caput should also be distinguished from capitis deminutio (reduction of legal head), which is the process or event by which legal personality is diminished, not the thing itself.
Why It Matters in Research
The term is a chameleon across the corpus. In Roman and civil law treatises, caput is a technical term of legal philosophy — the anchor concept for legal personality and status theory. In common law sources, particularly early English feudal and administrative materials, it shifts to concrete, institutional meanings: head of county, head of a lordship, a castle as the caput of a barony. Researchers reading across jurisdictions or time periods must first locate which tradition a source is operating in before any meaning can be fixed.
The estimatio capitis thread matters for wrongful death and damages research. The Saxon wergild framework encoded in that phrase has a surprisingly long tail; Anderson's connection of it to "modern" wrongful death damages reflects the 19th-century effort to translate ancient compensatory concepts into statutory frameworks. Researchers tracing the intellectual genealogy of wrongful death actions may find caput a useful point of entry.
The caput mortuum phrase in Webster's — the worthless chemical residue — appears occasionally in legal rhetoric and satire of the period as a term of abuse for nominal officials or spent legal entities. It is not a formal legal term but can appear in period texts in ways that momentarily look technical.
Per capita distribution entries in wills, trust instruments, and intestacy statutes will not typically use the word caput, but the underlying concept is always present. Understanding caput as the unit of legal personhood clarifies why per capita rules work the way they do and why early sources articulate them the way they do.
Historical Dictionary Support
All four source dictionaries agree on the core cluster of meanings: head, person, life, civil status. Black's (both editions) and Burrill converge closely, reflecting their shared reliance on the Roman and civil law tradition. Anderson's is distinctive in foregrounding estimatio capitis and drawing the line forward to modern wrongful death damages — a connection the other dictionaries leave implicit.
Burrill adds a useful doctrinal phrase: omnis noxalis actio caput sequitur — "every noxal action follows the person." This principle, that liability in Roman noxal actions attached to whoever currently held the wrongdoer (master, paterfamilias), illustrates how caput as "person" did concrete legal work in structuring liability rules, not merely as an abstract philosophical category.
What the historical dictionaries largely miss: the full feudal-administrative content of caput in English law. The identification of caput comitatis with the sheriff or the king gets a brief mention in Black's via Spelman, and the castle sense is noted, but none of the dictionaries develops the significance of caput as the head of a barony — the principal manor or castle from which a feudal lordship was reckoned. That usage is well-documented in feudal records and matters for property and land tenure research, but researchers will need to go beyond these dictionaries to treatises on feudal tenure to develop it fully.
Jurisdictional Note
Caput in its civil law (status and personality) sense is most directly relevant to research in Roman law, Scots law, Louisiana civil law, and other mixed or civilian jurisdictions. The common law castle and county-head senses are specifically English and are most relevant to feudal land law and early administrative history. American legal materials rarely use caput as a term of art; when it appears it is almost always in a per capita distributional context, where caput itself is implicit rather than stated.