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815

year

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General referenceInterpretive dossier study · Crown Archives visual atlas
Record originEnglish Wikipedia
Text licenseCC BY-SA 4.0
Source revisionApr 13, 2026
Entity authorityQ29917
Source-derived summary

Year 815 (DCCCXV) was a common year starting on Monday of the Julian calendar, the 815th year of the Common Era (CE) and Anno Domini (AD) designations, the 815th year of the 1st millennium, the 15th year of the 9th century, and the 6th year of the 810s decade.

Events

By place

Byzantine Empire

Byzantine–Bulgarian Treaty: Emperor Leo V the Armenian signs a 30-year peace agreement in Constantinople with Omurtag, ruler (khan) of the Bulgarian Empire. The Rhodope Mountains become the Byzantine border again, and Leo regains its lost Black Sea cities, after the Bulgars have them demolished.

Central America

April 2 – Sihyaj K'in Ich’aak II becomes the new ruler of the Mayan city state of Machaquila in Guatemala after the death of Ochk'in Kaloomte' Aj Ho' Baak, and reigns until early 824.

Europe

Hrafna-Flóki Vilgerðarson sets out from the Faroe Islands and discovers Iceland (documented later in the Landnámabók) (approximate date).

Britain

King Egbert of Wessex ravages the territories of the remaining British kingdom Dumnonia, known as the West Welsh (Cornwall).

Asia

Emperor Saga of Japan is the first sovereign to drink tea (according to legend), imported from China by monks. The upper classes adopt this beverage for medicinal use.

July 13 – Wu Yuanheng, Chinese chancellor of the Tang Dynasty, is murdered by assassins of warlord Wu Yuanji, in Chang'an.

By topic

Religion

Synod of Constantinople: A council led by patriarch Theodotus I, in the Hagia Sophia, reinstitutes iconoclasm.

Editorial summary

Begin with the source’s own compact description: “815” 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 242-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

Vocabulary and entity names are the principal evidence signals here, because they determine the precision of every later search. The source revision retrieved here is dated Apr 13, 2026. The linked authority identifier is Q29917. None of the 0 selected statements returned an explicit reference.

Critical limits

A concise general-reference account can conceal disagreements about scope, terminology or the weight assigned to individual sources. 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 “815”, its source revision and the description used here.
  2. Expand the search: follow 815 primary sources, 815 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 “815”?
  2. What terminology or title could unlock a more precise catalogue search?
  3. Which cited source is closest to the event, object or claim?
Subject index

Search terms from this dossier

Source & attribution

This entry incorporates text from 815” 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.