September 14
day of the year
September 14 is the 257th day of the year (258th in leap years) in the Gregorian calendar; 108 days remain until the end of the year.
Events
Pre-1600
AD 81 – Domitian became Emperor of the Roman Empire upon the death of his brother Titus.
775 – Leo IV the Khazar becomes Byzantine Emperor following the death of his father Constantine V.
786 – "Night of the three Caliphs": Harun al-Rashid becomes the Abbasid caliph upon the death of his brother al-Hadi. Birth of Harun's son al-Ma'mun.
919 – Battle of Islandbridge: High King Niall Glúndub is killed while leading an Irish coalition against the Vikings of Uí Ímair, led by King Sitric Cáech.
987 – Bardas Phokas the Younger rebels against Byzantine emperor Basil II and declares himself emperor.
1115 – Roger of Salerno's Crusader army defeats a numerically superior Seljuk army in the battle of Sarmin
1141 – An army of queen Matilda defeats and disperses an army of empress Matilda which was besieging Winchester. Robert of Gloucester is captured and exchanged for king Stephen, husband of queen Matilda.
1146 – Seljuk atabeg Imad al-Din Zengi of Mosul is assassinated by a slave and succeeded by his quarrelling sons.
1180 – Genpei War: In the Battle of Ishibashiyama in Japan, the new military commander of the Minamoto clan, Minamoto no Yoritomo, is routed by Ōba Kagechika of the Taira clan.
Begin with the source’s own compact description: “September 14” is day of the year. The dossier treats that line as a proposition to test through September and year, not as a finished interpretation.
Why this record matters
The phrase “day of the 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.
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 Sep 14, 2026. The linked authority identifier is Q2847. None of the 0 selected statements returned an explicit reference. The first chronological checks are 1600, 1115, 1141 and 1146.
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.
- Subject orientation
- Search vocabulary
- Locating named sources
The closest primary source, responsible institution and strongest cited specialist reference.
Three-step research path
- Establish the record: confirm the title “September 14”, its source revision and the description used here.
- Expand the search: follow September 14 primary sources, September 14 archive and September research across catalogues and specialist indexes.
- Test the account: compare the strongest cited source with the responsible institution’s current record and note any disagreement.
Questions for further research
- Which source most directly establishes the central claim about “September 14”?
- What terminology or title could unlock a more precise catalogue search?
- Which cited source is closest to the event, object or claim?
Search terms from this dossier
This entry incorporates text from “September 14” 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.