Definition
In historical English forest law, *passio* (also rendered as *pannage*) denotes the right or liberty for swine to enter and feed upon mast — the nuts, acorns, and fallen fruit of forest trees — within a forest or woodland. The term describes both the privilege itself and, by extension, the season during which that privilege was exercised. It is a term of the medieval common law of forests and belongs to the broader family of rights known as common of mast or pannage.
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Common Confusion
*Passio* and *pannage* are used interchangeably in the historical sources, but the relationship is not always cleanly synonymous. *Pannage* in medieval English forest law could refer both to the right of feeding swine on mast and to the payment or toll rendered to the lord in exchange for that right. *Passio*, as used in legal Latin contexts, emphasizes the liberty or license itself — the passage of hogs into the forest — rather than the monetary render. Researchers should not assume that every use of *pannage* in a primary source corresponds exactly to the liberty described by *passio*.
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Why It Matters in Research
*Passio* is a term almost exclusively confined to medieval and early modern forest law texts and manorial records. It will not appear in modern statutory compilations or contemporary case law. Researchers working in primary sources — forest eyre rolls, monastic charters, manorial custumals, or the *Monasticon Anglicanum* — may encounter it without cross-reference to more familiar English equivalents.
The term's significance lies in its connection to the intricate system of forest rights that governed English common lands from the Norman Conquest through the seventeenth century. Understanding *passio* requires situating it within the hierarchy of forest privileges: common of pasture, common of mast (pannage), common of estovers, and turbary. Confusing these rights in transcription or analysis is a well-documented research hazard.
The citation in both editions of Black's to *Monasticon Anglicanum* volume 1, page 682 (Dugdale's foundational compilation of English monastic records) signals that the term's primary evidentiary habitat is ecclesiastical and manorial grant documentation. Researchers should look for it in Latin-language instruments rather than in common law pleading records.
Nothing in this term survives into modern American or English law in recognizable form. Any apparent modern use is antiquarian or historical.
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Historical Dictionary Support
Both editions of Black's Law Dictionary give identical, minimal entries: "*Pannage*; a liberty for hogs to run in forests or woods to feed upon mast," with citation to *Mon. Angl.* 1, 682. The entries are purely definitional and make no attempt to trace the term's development, distinguish it from related forest rights, or note its obsolescence. Neither edition expands on the Latin derivation, the seasonal character of the right, or the toll dimension that attaches to pannage in other sources.
The concision here reflects the term's status as deep antiquarian material even at the time of Black's compilation. Both editions treat it as a curiosity of forest law vocabulary rather than a term with active practical significance. Researchers should not expect historical dictionaries to provide more than this threshold identification.
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Jurisdictional Note
*Passio* as a legal term has no operative presence in any American jurisdiction. It belongs entirely to English forest and manorial law and is encountered only in historical research contexts involving pre-modern English land tenure and forest administration.
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