Definition
De testamentis (Latin: "of testaments") is the title designating the fifth principal division of the Digests, or Pandects — the comprehensive compilation of Roman jurisprudence assembled under the Emperor Justinian in the sixth century. This section spans Books 28 through 36, inclusive, and collects the classical Roman jurists' writings on wills, testamentary succession, legacies, and related matters governing the disposition of property at death.
The term functions primarily as a bibliographic and structural label rather than a substantive legal doctrine. When encountered in legal texts, it directs the reader to a specific segment of the Corpus Juris Civilis and signals that the surrounding discussion draws on Roman testamentary law as systematized in that compilation.
Why It Matters in Research
Researchers will encounter de testamentis most often as a citation shorthand in treatises and commentaries on wills and succession written before the twentieth century, particularly works drawing on civilian or mixed legal traditions. Understanding that the term points to Books 28–36 of the Digest allows a researcher to trace doctrinal claims back to their Roman-law source rather than treating them as freestanding common-law authority.
The Digest as a whole is divided into several titled parts, and confusion between parts is common when citations are abbreviated or when transcription errors in manuscript sources drop book numbers. Knowing that de testamentis covers Books 28–36 helps distinguish it from adjacent sections dealing with obligations, property, or procedure. Researchers working in Louisiana, Quebec, South Africa, or Scotland — jurisdictions with civilian or mixed legal inheritances — are especially likely to find citations to this section in foundational succession-law commentary, where Roman testamentary rules exercised lasting influence on statutory and case-law development.
Because the term appears in historical dictionaries primarily as a taxonomic label, it will rarely appear as a substantive legal argument in pleadings or judicial opinions. Its research value is almost entirely organizational: it tells you where in the Digest to look, and it signals that an author is working within a civilian intellectual tradition.
Historical Dictionary Support
All three source dictionaries — Black's (1st and 2nd editions) and Burrill's — are in complete agreement. Each defines de testamentis identically as the title of the fifth part of the Digests or Pandects, covering Books 28 through 36 inclusive. No dictionary adds substantive doctrinal content, and none disagrees on the scope of the section. This uniformity reflects the purely descriptive, bibliographic nature of the term: there is nothing contested about its meaning, only about the content of the Roman texts it labels.
Burrill's entry is notable for immediately appending a separate entry — de theolonio — without transitional language, which illustrates the characteristic compression of nineteenth-century legal dictionaries and the risk of inadvertent conflation when reading closely printed historical sources.
None of the three dictionaries contextualizes the Digest's testamentary books within the broader structure of the Corpus Juris Civilis, nor do they identify which jurists' writings appear most prominently in Books 28–36. Researchers needing that level of detail should consult specialized Roman-law scholarship rather than general legal dictionaries.
Jurisdictional Note
The practical significance of de testamentis as a research marker varies by jurisdiction. In common-law systems, citations to this section of the Digest appear almost exclusively in historical or comparative scholarship. In civilian and mixed jurisdictions — including Louisiana, Quebec, and Scots law — the Roman testamentary rules systematized in Books 28–36 have more direct lineage to operative succession law and may be cited in foundational treatises that practitioners and courts still consult.