Definition
Sanguis (Latin: blood) carried two distinct legal meanings in civil and old English law.
1. Blood; consanguinity. The fact or condition of blood relationship between persons, used to describe kinship ties in contexts involving inheritance, descent, and family succession. In this sense, sanguis is the root concept underlying consanguinity doctrine — the shared bloodline that determined hereditary rights and the degree of relationship between potential heirs.
2. The jurisdictional right of a chief lord of the fee to hear and determine cases involving bloodshed on his lands. This was a species of high justice — a seigneurial power attached to certain feudal tenures granting the lord criminal jurisdiction over violent offenses committed within his fee. Possession of this right was a marker of elevated feudal authority and distinguished lords exercising high justice from those exercising only low justice.
Common Language
Modern common usage (Wiktionary): Sanguis is a Latin word meaning blood, used in English primarily in scientific, ecclesiastical, or literary contexts. It has no active legal meaning in modern English usage.
Historical common usage (Webster's 1913): Not entered as an English word; recognized as a Latin term meaning blood.
The gap between common and legal meaning here is the gap between a biological concept and a jurisdictional one. In legal Latin, sanguis was not merely descriptive of physical substance or kinship — it named a formal power of lordship. A researcher encountering sanguis in a feudal charter or survey cannot assume the term refers simply to blood relationship; context will determine whether it signals a hereditary claim or a lord's criminal jurisdiction over violent offenses.
Common Confusion
Sanguis (jurisdictional right over bloodshed) should not be confused with the broader feudal concept of alta justitia (high justice) generally, nor with furcas et fossa (gallows and pit), which referenced capital punishment jurisdiction. Sanguis specifically named the right to adjudicate cases where blood was shed, and its presence or absence in a grant of jurisdiction was significant. Researchers should also distinguish sanguis as consanguinity — the kinship doctrine — from cognatio, which described relationship through the mother's line in civil law, and agnatio, which described relationship through the father's line.
Why It Matters in Research
Researchers will encounter sanguis in two very different document types: feudal surveys and charters (where it names a jurisdictional right) and civil law texts and inheritance disputes (where it names the bloodline relationship between parties). Misreading the jurisdictional sense as merely descriptive of blood will produce a fundamental misunderstanding of the document's legal content.
In feudal records — particularly English surveys, monastic cartularies, and Norman and Anglo-Norman charters — the phrase sanguis or variations like habere sanguinem signals a grant or claim of criminal jurisdiction. The Monasticon Anglicanum citation in the historical sources reflects this: such entries typically appear in the context of listing the franchises and liberties attached to a particular fee.
In civil law inheritance contexts, sanguis operates as a technical term of consanguinity doctrine and connects directly to degree-of-relationship calculations used to determine the order of succession among collateral heirs. This sense of sanguis feeds into a larger vocabulary — consanguinitas, propinquitas, gradus — that structured Roman and later canon law inheritance rules.
The term has no currency in modern Anglo-American law. Researchers should treat it as a term of art confined to medieval and early modern sources. Where it appears in English translation, it will typically be rendered as "blood" or "right of blood," which can obscure its technical feudal-jurisdictional meaning.
Burrill adds an important subsidiary usage not found in the other sources: sanguinem redimere, to redeem one's blood, meaning the payment of merchet — the customary fine a servile tenant paid to the lord for permission to give a daughter in marriage outside the manor. This phrase locates sanguis within the law of villeinage and unfree tenure, a distinct third context that neither Black's nor Bouvier captures.
Historical Dictionary Support
The historical sources largely agree on the two core meanings — blood/consanguinity and jurisdictional right over bloodshed — but they distribute their emphasis differently. Black's (1st Ed.) gives both meanings. Bouvier gives only the jurisdictional meaning, effectively treating sanguis as a term of feudal franchise law. Black's (2nd Ed.) reverts to the narrower gloss of blood and consanguinity alone. Burrill is the most expansive, adding the sanguinem redimere usage and connecting the term to Blackstone's treatment of villeinage tenure.
None of the historical sources adequately treat sanguis as a term of Roman civil law consanguinity doctrine, which is the context in which it appears most frequently in the civil law sources underlying later European and canon law succession rules. Researchers working in civil law materials will find the dictionary entries incomplete guides and should consult Justinian's Institutes and the Digest directly for the consanguinity doctrine, where sanguis operates as a foundational term.
Jurisdictional Note
The jurisdictional meaning of sanguis — the lord's right to judge bloodshed cases — belongs almost entirely to Norman, Anglo-Norman, and early English feudal law. It has no equivalent in modern common law jurisdictions. The consanguinity meaning survives as a concept in modern succession law but is expressed in English terminology; the Latin term itself is obsolete in contemporary practice.