Editing 451 (section)

== Events ==
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=== By place ===
==== Europe ====
* Spring – [[Attila]] gathers his [[vassal]]s—[[Bastarnae]], [[Gepids]], [[Heruli|Heruls]], [[Ostrogoths]], [[Rugians]], [[Sciri]]ans and [[Thuringians]] (among others), and smashes through [[Germany]], causing widespread panic and destruction. He arrives in [[Gallia Belgica|Belgica]] with an army (50,000 men) and crosses the [[Rhine]].{{citation needed|date=February 2024}}
* [[April 7]] – Attila's forces invade [[Gaul]] and sack [[Metz]]. The major cities of [[Strasbourg]], [[Worms, Germany|Worms]], [[Mainz]], [[Trier]], [[Cologne]], [[Reims]], [[Tournai]], [[Cambrai]], [[Amiens]] and [[Beauvais]] are destroyed by the [[Huns]].{{citation needed|date=February 2024}}
* [[Eudocia (daughter of Valentinian III)|Eudocia]], daughter of Emperor [[Valentinian III]], marries [[Huneric]] in [[Ravenna]]. The engagement serves to strengthen the [[Military alliance|alliance]] between the [[Western Roman Empire]] and the [[Vandal Kingdom]].{{citation needed|date=February 2024}}
* [[June]] – Attila approaches ''Aurelianum'' (modern [[Orléans]]) and the city's inhabitants close the gates, forcing him to lay [[siege]]. After learning of the Hun invasion, [[Flavius Aetius]] (''[[magister militum]]'') moves quickly from [[Italy]] into Gaul, and joins forces with  [[Visigoths|Visigoth]] king [[Theodoric I]].{{citation needed|date=February 2024}}
* [[June 20]] – [[Battle of the Catalaunian Plains]] (Châlons): Attila avoids a pitched battle near Orléans, and withdraws to the Catalaunian Plains ([[Champagne-Ardenne]]). The Roman [[coalition]] defeats the Huns, but Theodoric I is killed in the encounter. This is one of the last military victories of the Western Roman Empire, before the victories of Emperor [[Majorian]] against the Alemanni, Visigoths, Suebi and Burgundians, between 457 and 461.{{citation needed|date=February 2024}}
* [[Thorismund]] succeeds his father [[Theodoric I]] as king of the Visigoths. He is crowned in the capital at [[Toulouse]], and extends the [[Visigothic Kingdom]] in [[Hispania]].{{citation needed|date=February 2024}}

==== Persia ====
* [[May 26]] – [[Battle of Avarayr|Battle of Vartanantz]]: King [[Yazdegerd II]] defeats the  [[Armenians|Armenian]] army (66,000 men) under their rebel leader [[Vardan Mamikonian|Vartan Mamikonian]] on the [[Avarayr Plain]] ([[Armenia]]). Despite the loss of Mamikonian, who is killed, the Armenians consider this battle to have been a moral and [[Religion|religious]] victory, since Yazdegerd, out of respect for their efforts, allows them to remain [[Christians|Christian]]. The anniversary is a national and religious holiday.{{citation needed|date=February 2024}}
* Yazdegerd II issues a [[decree]] to abolish the [[Shabbat]], and orders the execution of [[Jews|Jewish]] leaders, including the [[Exilarch]].{{citation needed|date=February 2024}}

=== By topic ===
==== Religion ====
* [[October 8]] – [[November 1]] – [[Council of Chalcedon]], an [[ecumenical council]] of the Church: The [[monophysitism]] of [[Eutyches]] is repudiated, and the [[Chalcedonian Definition]] set forth. As a result of this council, the [[Oriental Orthodox]] Churches eventually become a separate communion. More immediately, [[Jerusalem]] becomes a [[List of Armenian Patriarchs of Jerusalem|Patriarchate]], and [[Dioscorus of Alexandria]] is deposed as [[Patriarch of Alexandria]] by the Council.<ref>{{cite book|first=Mark|last=DelCogliano|chapter=Acts of the Council of Calcedon (451): Selected Proceedings and the Chalcodon Definition|title=The Cambridge Edition of Early Christian Writings: Volume 4, Christ: Chalcedon and Beyond|publisher=Cambridge University Press|location=Cambridge|year=2022|url=https://books.google.com/books?id=LxhdEAAAQBAJ|pages=49–50|isbn=978-1-31651-114-5}}</ref>