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Treason Act 1351

United Kingdom legislation

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General referenceInterpretive dossier study · Crown Archives visual atlas
Record originEnglish Wikipedia
Text licenseCC BY-SA 4.0
Source revisionAug 15, 2026
Entity authorityQ3998167 ↗
Source-derived summary

The Treason Act 1351 (25 Edw. 3 Stat. 5. c. 2) is an act of the Parliament of England where, according to William Blackstone, common law treason offences were enumerated and no new offences were created. It is one of the earliest English statutes still in force, although it has been very significantly amended. It was extended to Ireland in 1495 and to Scotland in 1708. The act was passed at Westminster in the Hilary term of 1351, in the 25th year of the reign of Edward III and was entitled "A Declaration which Offences shall be adjudged Treason". It was passed to clarify precisely what was treason, as the definition under common law had been expanded rapidly by the courts until its scope was controversially wide. The act was last used to prosecute William Joyce, better known as "Lord Haw-Haw", in 1945 for collaborating with Germany in World War II.

The act is still in force in the United Kingdom.

Editorial summary

Begin with the source’s own compact description: “Treason Act 1351” is united Kingdom legislation. The dossier treats that line as a proposition to test through Treason, United and Kingdom, not as a finished interpretation.

Editorial reviewA practical starting point whose main value is the path it opens into stronger specialist and primary sources. The current lead gives the account dated anchors—1351, 1495, 1708, 1945—that can be checked directly. The linked authority record independently contributes the date 1351-01-01. For this dossier, Treason, United and Kingdom is the immediate research focus.
Editorial analysis

Why this record matters

The phrase “united Kingdom legislation” supplies a clear boundary for inquiry. It also exposes the unanswered questions: who defined that boundary, when it became stable and which sources sit outside it.

Evidence profile

Named sources, stable identifiers and responsible institutions provide the strongest route from overview to verifiable evidence. The source revision retrieved here is dated Aug 15, 2026. The linked authority identifier is Q3998167. None of the 1 selected statements returned an explicit reference. The first chronological checks are 1351, 1495, 1708 and 1945.

Critical limits

The absence of detail may reflect summary conventions rather than a lack of surviving documentation. The source lead contains qualifying language; that uncertainty should survive quotation, summary and reuse. Authority statements aid reconciliation but still require their own references, qualifiers and ranks to be checked.

How to read it

Use the entry as an orientation point, then follow its citations and revision history. Names, dates and institutional relationships should be checked against the original record.

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  2. Expand the search: follow Treason Act 1351 primary sources, Treason Act 1351 archive and Treason research across catalogues and specialist indexes.
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Source & attribution

This entry incorporates text from “Treason Act 1351” on English Wikipedia. Contributors are listed in the page history. Text is available under the Creative Commons Attribution-ShareAlike 4.0 License. Selected authority identifiers and statements are retrieved from Wikidata under CC0; their references and qualifiers remain part of the verification path.