September 9
day of the year
September 9 is the 252nd day of the year (253rd in leap years) in the Gregorian calendar; 113 days remain until the end of the year.
Events
Pre-1600
337 – Constantine II, Constantius II, and Constans succeed their father Constantine I as co-emperors. The Roman Empire is divided between the three Augusti.
1000 – Battle of Svolder during the Viking Age.
1141 – Yelü Dashi, the Liao dynasty general who founded the Qara Khitai, defeats the Seljuq and Kara-Khanid forces at the Battle of Qatwan.
1320 – In the Battle of Saint George, the Byzantines under Andronikos Asen ambush and defeat the forces of the Principality of Achaea, securing possession of Arcadia.
1488 – Anne becomes sovereign Duchess of Brittany, becoming a central figure in the struggle for influence that leads to the union of Brittany and France.
1493 – Battle of Krbava Field, a decisive defeat of Croats in Croatian struggle against the invasion by the Ottoman Empire.
1493 – Christopher Columbus, with 17 ships and 1,200 men, sails on second voyage from Cadiz.
1499 – The citizens of Lisbon celebrate the triumphal return of the explorer Vasco de Gama, completing his two-year journey around the Cape of Good Hope to India.
This brief starts where responsible research should: with the source description of “September 9” as day of the year. Everything that follows is an evidence route, not borrowed authority.
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The subject matters to the general reference register because the source frames it as day of the year. Its deeper value depends on whether names, dates, institutions and citations support that framing.
Named sources, stable identifiers and responsible institutions provide the strongest route from overview to verifiable evidence. The source revision retrieved here is dated Sep 18, 2026. The linked authority identifier is Q2856. None of the 0 selected statements returned an explicit reference. The first chronological checks are 1600, 1000, 1141 and 1320.
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This entry incorporates text from “September 9” 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.