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240

year

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General referenceInterpretive dossier study · Crown Archives visual atlas
Record originEnglish Wikipedia
Text licenseCC BY-SA 4.0
Source revisionAug 25, 2026
Entity authorityQ30032
Source-derived summary

Year 240 (CCXL) was a leap year starting on Wednesday of the Julian calendar. At the time, it was known as the Year of the Consulship of Sabinus and Venustus (or, less frequently, year 993 Ab urbe condita). The denomination 240 for this year has been used since the early medieval period, when the Anno Domini calendar era became the prevalent method in Europe for naming years.

Events

By place

Roman Empire

The Roman Empire is threatened on several fronts at the same time. Africa revolts and tribes in northwest Germania, under the name of the Franks, are raiding the Rhine frontier.

Persia

April 12 – Prince Shapur I becomes co-ruler of the Sasanian Empire with his father King Ardashir I.

Siege of Hatra: The Sasanians besiege the capital of the Kingdom of Hatra ruled by Sanatruq II.

India

Maharaja Sri-Gupta becomes ruler of the Gupta Empire (approximate date).

By topic

Religion

Mani, a young mystic of Ctesiphon, proclaims himself a prophet at the court of Ardashir I. He preaches his doctrine, Manichaeism, throughout the Sassanid Empire.

Births

Lucian of Antioch, Syrian theologian and martyr (d. 312)

Sporus of Nicaea, Greek mathematician (approximate date)

Zenobia, queen of the Palmyrene Empire (d. 274)

Deaths

Ammonius Saccas, Neoplatonic philosopher (approximate date)

Herodian of Antioch, Roman historian and writer (b.

Editorial summary

Begin with the source’s own compact description: “240” is year. The dossier treats that line as a proposition to test through year, not as a finished interpretation.

Editorial reviewA concise reference frame for defining the subject, testing terminology and identifying the institution closest to the evidence. The current 217-word lead offers orientation but no explicit four-digit date, so chronology should not be assumed. The selected authority fields contribute no independent date. For this dossier, year is the immediate research focus.
Editorial analysis

Why this record matters

The phrase “year” 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 25, 2026. The linked authority identifier is Q30032. None of the 0 selected statements returned an explicit reference.

Critical limits

The absence of detail may reflect summary conventions rather than a lack of surviving documentation. The lead is largely declarative, so disagreement and counter-evidence require a deliberate search beyond the opening account. 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.

Best used for
  • Subject orientation
  • Search vocabulary
  • Locating named sources
Verify next

The closest primary source, responsible institution and strongest cited specialist reference.

Three-step research path

  1. Establish the record: confirm the title “240”, its source revision and the description used here.
  2. Expand the search: follow 240 primary sources, 240 archive and year research across catalogues and specialist indexes.
  3. Test the account: compare the strongest cited source with the responsible institution’s current record and note any disagreement.

Questions for further research

  1. Which source most directly establishes the central claim about “240”?
  2. Which cited source is closest to the event, object or claim?
  3. What terminology or title could unlock a more precise catalogue search?
Subject index

Search terms from this dossier

Source & attribution

This entry incorporates text from 240” 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.