Definition
Latin. In Roman civil law, children of unknown or legally impermissible paternity — commonly rendered as "spurious children" or bastards. The term describes offspring born of promiscuous or illicit cohabitation who either cannot identify their father or whose identified father is one they are legally prohibited from having (for example, a father whose relationship with the mother was forbidden by law). Such children were considered to have no legal father and consequently stood outside the ordinary rules of Roman inheritance, guardianship, and family status that depended on established paternal descent.
The term appears interchangeably in historical sources with VULGO QUAESITI ("gotten from the people"), which emphasizes the promiscuous character of the conception. Both phrases carry the same operative legal meaning: children without cognizable paternal lineage for purposes of civil law.
Common Confusion
VULGO CONCEPTI and VULGO QUAESITI are treated as synonyms in most historical legal dictionaries, but the phrasing carries a slight distinction in emphasis. Vulgo concepti focuses on the manner of conception (among the common crowd); vulgo quaesiti focuses on the manner of acquisition or seeking (sought from the people). The Digest uses both. Researchers should not assume one term is broader or narrower than the other when reading Roman or civil-law sources — the legal consequences attached to each were identical.
Neither term is equivalent to the broader English legal category of "bastard" without qualification. English common law used "bastard" for any child born outside valid marriage, regardless of whether the father was identifiable. Vulgo concepti is narrower: it contemplates specifically the absence or legal impermissibility of paternity, not merely illegitimacy in the common-law sense. A child born of an adulterous but otherwise identifiable union was illegitimate under Roman law but would not necessarily be described as vulgo conceptus.
Why It Matters in Research
This term surfaces almost exclusively in civil-law and Roman-law contexts and in English legal dictionaries that incorporated civil-law vocabulary. Researchers will encounter it in:
— Treatises on Roman private law discussing the law of persons and inheritance, where the status of vulgo concepti determined succession rights (or their absence).
— Historical Louisiana, Quebec, and other mixed-jurisdiction sources where civil-law concepts of illegitimacy were applied alongside or against common-law categories.
— Comparative illegitimacy scholarship, particularly 19th-century works examining how different legal systems treated children born outside recognized unions.
— Canonical and ecclesiastical law discussions that borrowed civil-law terminology to describe children whose parentage precluded legitimate status.
The primary research trap is assuming that vulgo concepti maps cleanly onto the common-law category of "bastard" or onto modern legal concepts of non-marital children. The Roman concept was specifically about the recognizability and legality of the paternal relationship — not merely the absence of marriage. This distinction matters in historical legal analysis but has no direct modern legal application in American or English law.
The term has no living statutory or case-law use in American jurisdictions. It appears in modern legal dictionaries only as a historical reference.
Historical Dictionary Support
The three source dictionaries converge on the core definition but differ usefully in depth. Black's (both editions) gives the bare minimum: spurious children, bastards, with a nod to the civil-law context. Burrill adds the most analytically useful detail, quoting the Digest formulation directly: children "qui patrem demonstrare non possunt, vel qui possunt quidem, sed eum habent quem habere non licet" — those who cannot point to a father, or who can but have one whom it is not lawful to have. This two-part formulation from Digest 1.5.23 is the operative Roman-law definition and is worth noting for researchers working with primary civil-law sources.
All three dictionaries cross-reference VULGO QUAESITI without clearly distinguishing the two, which is accurate — the terms function as synonyms in the Roman sources. The Institutes references (Inst. 3.4.3; 3.5.4) cited in Black's concern the succession rights of mothers to their illegitimate children, a context that illustrates the practical legal stakes of the classification.
What the historical dictionaries do not address: the procedural mechanisms by which Roman law determined whether a child fell into this category, the varying treatment of vulgo concepti under different emperors' legislation, or the term's migration into canon law and early modern civil-law systems. Researchers needing that depth should move beyond the dictionary shelf to treatises on Roman private law.
Jurisdictional Note
This is a Roman civil-law term with no operative modern jurisdiction. Its relevance to American legal research is historical and comparative. Louisiana courts and scholars occasionally encountered civil-law illegitimacy concepts in 19th-century inheritance disputes, but modern Louisiana law has reformed illegitimacy doctrine entirely. Researchers should treat any appearance of this term in case law or pleadings as a signal that the source is drawing on civilian rather than common-law authority.