Definition
De conflictu legum (Latin: "concerning the conflict of laws") is a bibliographic and doctrinal phrase identifying a body of legal literature addressing how courts resolve disputes when the laws of two or more jurisdictions apply to the same matter. The phrase functions primarily as a title designation — several foundational treatises on private international law and choice-of-law doctrine carried this phrase as their title or subtitle. By extension, the term describes the subject matter itself: the theoretical and practical framework for determining which jurisdiction's law governs a transaction, relationship, or dispute with multi-jurisdictional elements.
Why It Matters in Research
Researchers encounter de conflictu legum most often in footnotes, bibliographic references, and older treatise citations rather than in case law or statutes. Its primary research function is as a pointer to early conflict-of-laws literature. When a 19th-century court or commentator cites a work "de conflictu legum," they are referencing a treatise tradition — not a statute, rule, or case.
The Kent reference in all three dictionary sources (2 Kent, Comm. 455) is the anchor citation in American legal literature. James Kent's Commentaries on American Law, volume 2, was a standard source for conflict-of-laws doctrine in American courts through much of the 19th century. A researcher following this citation will find Kent synthesizing the earlier European civilian and Scottish treatise tradition — the same tradition the Latin phrase itself descends from.
Corpus trap: Because de conflictu legum appears in historical sources as a title-phrase rather than a term of art with operative legal meaning, searching for it in case databases will return little. Its natural habitat is treatises, law review articles on the history of private international law, and bibliographic footnotes. Researchers working on the history of choice-of-law doctrine should treat it as a bibliographic key rather than a searchable legal term.
The phrase connects directly to the broader evolution from comity-based conflict-of-laws theory (dominant through Story and Kent) toward the more systematic vested rights and interest-analysis approaches of the 20th century. Works titled or subtitled de conflictu legum represent the earliest stratum of that analytical tradition.
Historical Dictionary Support
All three dictionary sources — Black's (1st and 2nd editions) and Burrill — give virtually identical entries: a Latin gloss, an identification of the phrase as a treatise title, and the Kent citation. The uniformity confirms this was understood as a bibliographic term of art rather than a doctrine with contested definition. None of the sources attempt to define the underlying conflict-of-laws subject matter at length within this entry, treating that as a separate subject covered elsewhere.
What the historical dictionaries do not provide is any identification of which specific works bore this title. The tradition includes civilian writers in the Dutch and German schools of private international law, where the phrase circulated before American treatise writers adopted it. Researchers seeking those sources will need to move beyond the dictionary entries to Kent himself and to histories of private international law scholarship.
Black's 2nd edition reproduces the entry without alteration from the 1st edition, suggesting the phrase had stabilized in bibliographic usage and no new doctrinal development had modified its meaning between editions.
Jurisdictional Note
The phrase has no jurisdiction-specific legal meaning. It describes a genre of legal scholarship applicable across common law and civil law systems. American, English, and continental European legal writers all used similar phrases when addressing choice-of-law problems, though the underlying doctrines they developed diverged substantially.
Encyclopedia Cross-Reference
Law Mind Encyclopedia — Conflict of Laws
Law Mind Encyclopedia — Private International Law
Law Mind Encyclopedia — Choice of Law