940
year
Year 940 (CMXL) was a leap year starting on Wednesday of the Julian calendar.
Events
By place
Europe
The tribe of the Polans begins the construction of the following fortified settlements (Giecz, Bnin, Ląd, Gniezno, Poznań, Grzybowo and Ostrów Lednicki) in Greater Poland. The Piast Dynasty under Duke Siemomysł gains control over other groups of Polans along the Upper Vistula, and establishes their rule around Giecz (approximate date).
Japan
March 25 – Taira no Masakado, the self-proclaimed "New Emperor" (新皇), is subdued by local rivals who revolt against his rule. His forces are defeated by his cousin, Taira no Sadamori, in Shimōsa Province. Masakado's head is brought back to Emperor Suzaku in Tokyo.
By topic
Literature
Saadia Gaon, a Jewish rabbi and philosopher, compiles his Siddur (Jewish prayer book) in Arabic and synagogal poetry in modern-day Iraq (approximate date).
Religion
Narita-san ("New victory temple"), a Shingon Buddhist temple, is founded in Chiba (Japan).
Births
June 10 – Abu al-Wafa' Buzjani, Persian mathematician and astronomer (d. 998)
Abdollah ibn Bukhtishu, Syrian physician and scientist (d.
“940” enters the record as year. Crown Archives preserves that source wording while asking what year can confirm, complicate or overturn.
Why this record matters
“940” is worth following because a concise public description often conceals a longer documentary argument. Here, year provides the most credible route into that argument.
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 Mar 3, 2026. The linked authority identifier is Q23830. None of the 0 selected statements returned an explicit reference.
Overview language is designed for orientation and should not be treated as a substitute for the evidence cited beneath it. 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 “940”, its source revision and the description used here.
- Expand the search: follow 940 primary sources, 940 archive and year 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 “940”?
- Which institution is responsible for the underlying evidence?
- What terminology or title could unlock a more precise catalogue search?
Search terms from this dossier
This entry incorporates text from “940” 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.