Definition
In seysina is a Latin-French legal phrase meaning "in seisin" — that is, in actual, present possession of lands. The phrase describes the condition of a person who holds or has placed himself in lawful physical possession of real property, as understood under the feudal common law of land tenure.
The phrase appears in two closely related constructions in early land law:
1. Tenere se in seysina — to hold oneself in seisin; to maintain or continue one's possession of land against interference or dispossession.
2. Se ponere in seysinam — to put oneself into seisin; to take or enter into possession of land.
Both constructions point to the same underlying concept: seisin as an active, maintained state of physical occupation and legal entitlement, not merely an abstract claim of title.
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Common Language
The phrase has no living common usage. Its component Latin and Law French elements are archaic outside legal and historical scholarship. No Webster's 1913 or Wiktionary definitions apply.
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Common Confusion
In seysina should not be confused with a mere claim of ownership or title. Under feudal land law, a person could have title without seisin (as in cases of disseisin), and seisin without a clear superior title. The phrase describes a factual condition of possession with legal recognition, not a declaration of ownership in the modern sense. Researchers encountering this phrase in early pleadings or treatises should resist reading it through a modern property lens.
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Why It Matters in Research
This phrase is exclusively a term of the medieval and early modern common law of real property. It will appear almost entirely in pre-modern sources — Bracton above all, whose De Legibus et Consuetudinibus Angliae (circa 13th century) is the primary locus for both constructions — and in early English and colonial American pleadings where the forms of real actions survived long after feudal tenure itself had eroded.
Researchers should be alert to the following:
First, the Law French connection matters for reading sources. Burrill notes that in seysina is the Latin form, and that the Law French equivalent is the single word eins, with the English "in" functioning as a direct translation. Across different manuscripts and digests, the same concept may appear in any of these three linguistic registers. Variant spellings — seisina, seysina, seysine, seisin — are common and do not signal different legal meanings.
Second, the phrase marks a procedural and substantive threshold. In the real actions of the common law (novel disseisin, mort d'ancestor, and related writs), the question of whether a party was in seysina at the relevant moment was often dispositive. A plaintiff needed to establish that he had been seised — in seysina — before being wrongfully ejected. Defendants used the phrase to assert continuing seisin and thereby defeat the action. Understanding the phrase is essential to parsing these pleadings correctly.
Third, the concept of seisin itself transformed over centuries. What Bracton describes in the 13th century is considerably more feudal in texture than what equity courts and eventually common law courts treated as seisin in the 17th and 18th centuries. Researchers using in seysina as a search term in the Law Mind corpus should expect a tight clustering around Bracton-era sources and early common law treatises, with the phrase fading from use as modern conveyancing vocabulary replaced it.
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Historical Dictionary Support
Burrill's Law Dictionary provides the sole historical dictionary treatment of this specific phrase. Burrill correctly identifies it as Latin-French hybrid terminology, grounds it in Bracton, and supplies the two principal constructions. The entry is compact but accurate. Burrill's gloss that the English word "in" is a mere translation of the Law French eins is a useful philological note that helps explain why the same concept appears across sources in three different languages without terminological change.
What Burrill does not address — and what no single dictionary entry adequately captures — is the procedural significance of the phrase in the real actions, or the conceptual weight that seisin carried as the organizing principle of feudal land law. For that, researchers must move from dictionary sources to treatise literature, with Bracton, Littleton's Tenures, and Coke upon Littleton as the foundational texts.
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Jurisdictional Note
This phrase is rooted in English common law and appears primarily in English and early Anglo-American legal sources. It has no meaningful modern jurisdictional variation because the feudal real actions in which it appeared were abolished in England by the Real Property Limitation Act 1833 and had largely died out in American practice well before that. Louisiana, which followed civil law traditions, would have had no occasion to use this terminology.
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