Definition
Custuma antiqua sive magna (Latin: "ancient or great customs") refers to the earliest formalized customs duties levied by the English crown on the export of wool, wool-pelts (sheep-skins bearing wool), and leather. These duties applied to all merchants trading such commodities out of England — both native English merchants and foreign merchant strangers — with the distinction that merchant strangers paid a surcharge of one-half more than their native counterparts. The custuma antiqua sive magna represents one of the foundational revenue mechanisms of medieval English commercial regulation, predating and distinct from later systems of parliamentary taxation on trade.
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Common Confusion
The term sits within a cluster of overlapping medieval customs terminology that researchers frequently conflate. The custuma antiqua sive magna (ancient or great customs) should not be confused with the custuma nova (new or petty customs), which were later duties imposed on a broader range of imported and exported goods under Edward I's Carta Mercatoria of 1303, or with tunnage and poundage, the parliamentary grants on wine and general merchandise that became a separate and politically contentious revenue stream in the Tudor and Stuart periods. The "magna" (great) designation refers to the economic importance and primacy of the wool trade to the medieval English economy, not to any connection with Magna Carta.
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Why It Matters in Research
This term is primarily encountered in historical legal research touching on medieval English fiscal administration, the wool trade, and the constitutional development of the crown's prerogative taxing powers. Several research traps are worth flagging:
**Periodization matters.** The custuma antiqua sive magna originated in the late thirteenth century under Edward I, formalized around 1275 by the Statute of Westminster and related customs legislation. Researchers working in sources predating this period will not encounter the term in its technical sense; post-1275 sources use it with increasing precision.
**The native/stranger distinction is legally significant.** The differential duty rate applicable to merchant strangers is not merely a historical curiosity — it reflects the legal status of alien merchants in medieval English law, a category with distinct rights, disabilities, and procedural treatment. Researchers tracing the development of alien merchant status, the staple system, or the law merchant will find the custuma antiqua sive magna directly relevant.
**Blackstone is the primary secondary bridge.** Black's 2nd edition cites 1 Bl. Comm. 314, making Blackstone's Commentaries the key secondary source connecting this medieval revenue term to the broader common law tradition. Researchers should consult Blackstone directly for narrative context, but should then work backward into the primary exchequer and customs records for documentary evidence.
**Wool's centrality to medieval English law and finance.** The wool export trade underpinned a significant portion of the English crown's ordinary revenue in the thirteenth and fourteenth centuries. Understanding the custuma antiqua sive magna is essential context for research into the financial relationship between the crown and the merchant community, the emergence of parliamentary control over taxation, and the history of the English staple towns.
**The term disappears from active legal usage** well before the modern period. Researchers encountering it in sources after the sixteenth century are almost certainly dealing with historical or antiquarian references rather than operative legal instruments.
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Historical Dictionary Support
Black's Law Dictionary (2nd Ed.) provides a compact and accurate entry, defining custuma antiqua sive magna as duties on wool, sheep-skin or wool-pelts, and leather, payable by all merchants but at a higher rate for merchant strangers. The sole authority cited is Blackstone's Commentaries (1 Bl. Comm. 314), which situates these duties within the crown's prerogative revenue and the broader framework of English customs history.
The Black's entry, while reliable as a pointer, is characteristically spare. It does not address the statutory origins of these duties, the administrative machinery of the medieval customs (the collectors of customs, the role of the staple), or the constitutional controversies over whether the crown could levy such duties without parliamentary assent — controversies that became acute in the Ship Money debates and earlier disputes over impositions. Researchers should treat the Black's entry as an orientation, not a terminus.
No entry for this term appears in later editions of Black's with appreciably more depth, consistent with its status as a term of purely historical rather than operative modern legal significance.
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Jurisdictional Note
This term is specific to English legal history and has no direct counterpart or application in American, Scottish, or other common law jurisdictions. It is irrelevant to modern customs law in any jurisdiction.
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