Definition
Chronicon Pretiosum (Latin: "precious chronicle") is the title of a historical treatise written by William Fleetwood, Bishop of Ely, published in 1707. The work surveys the value of money and the price of commodities at various periods in English history, providing a systematic record of monetary purchasing power from medieval times through the early eighteenth century. In legal contexts, the work was cited as an authoritative reference for understanding the real value of sums mentioned in historical statutes, contracts, deeds, and other legal instruments — particularly where fixed monetary figures had been rendered misleading or meaningless by centuries of inflation and currency change.
Why It Matters in Research
Researchers working in early English legal history, property law, or statutory construction will encounter the Chronicon Pretiosum as a citation anchor rather than a substantive legal authority. Its function in legal sources is almost entirely interpretive and contextual: when historical legal writers needed to explain what a sum — a pound, a mark, a shilling — actually represented in terms of real purchasing power at the time a statute was enacted or a deed was executed, Fleetwood's work was the standard reference.
The most significant navigational point is that Blackstone cites the Chronicon Pretiosum at 1 Bl. Com. 173, lending it the weight of canonical secondary authority in the common law tradition. Any researcher tracing Blackstone's commentary on historical statutory interpretation or the adequacy of ancient monetary thresholds should be aware that Blackstone's confidence in these figures rests substantially on Fleetwood. That chain of reliance matters: downstream citations in American and English cases that repeat Blackstone's monetary observations may ultimately trace back to a single early eighteenth-century source with its own methodological limitations.
The practical trap for corpus researchers is treating the Chronicon Pretiosum as a legal authority rather than what it is: a piece of historical economic scholarship that legal writers adopted as a convenient reference. It has no binding legal force. When encountered in primary legal sources, it signals that the surrounding passage is addressing the historical adequacy or meaning of a monetary amount — not a point of legal doctrine. Researchers should read such passages as interpretive commentary, not as statements of rule.
The work also illustrates a broader phenomenon in pre-nineteenth-century legal writing: the regular incorporation of non-legal scholarly sources (ecclesiastical, historical, economic) into legal argument and treatise writing. This cross-disciplinary citation practice is common in Blackstone, Coke, and their contemporaries, and modern researchers should not mistake it for the kind of authority citation that would appear in a contemporary brief or judgment.
Historical Dictionary Support
Burrill's Law Dictionary provides a compact and accurate identification of the work: a treatise by Bishop Fleetwood showing the value of money at different periods in English history, with the Blackstone citation appended. This entry is representative of how mid-nineteenth-century American law dictionaries treated the Chronicon Pretiosum — as a reference work worth identifying and locating but not requiring extended analysis.
Burrill's entry does not discuss the substance of Fleetwood's findings or the methodology behind his monetary valuations, and it does not flag any debate about the work's reliability. Historical legal dictionaries generally treat the Chronicon Pretiosum as uncontroversial background material. What they miss is the downstream significance of the Blackstone citation: because 1 Bl. Com. 173 is itself a heavily consulted passage on the interpretation of old statutes, the Chronicon Pretiosum enters legal research not primarily through direct citation but through Blackstone's authority, making it an invisible source behind a visible one.
Jurisdictional Note
The Chronicon Pretiosum is exclusively a reference point in English legal history and in American legal writing that draws on Blackstone's Commentaries. It has no independent application in modern legal proceedings in any jurisdiction.