Editing 1257 (section)

== Events ==
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=== By place ===

==== Europe ====
* [[January 13]] &ndash; At the first recorded meeting of the college of the seven [[Prince-elector|Electors]] of the [[Holy Roman Empire]], the 48-year-old [[Richard of Cornwall]] (the brother of King [[Henry III of England]]) is elected [[King of the Romans]]. He is crowned at [[Aachen]], on [[May 17]]. His candidacy is opposed by King [[Alfonso X of Castile]] ("the Wise"), [[Pope Alexander IV]] and King [[Louis IX of France]] ("the Saint") who favour Alfonso, but both are ultimately convinced by Richard's sister-in-law, Queen [[Eleanor of Provence]], to support Richard.<ref>Hywel Williams (2005). ''Cassell's Chronology of World History'', p. 143. {{ISBN|0-304-35730-8}}.</ref>
* Spring &ndash; The [[Epirote–Nicaean conflict (1257–59)]] begins between the [[Despotate of Epirus]] and the [[Empire of Nicaea]]. Despot [[Michael II Komnenos Doukas]] revolts and defeats the Nicaean army under [[George Akropolites]]. The Epirote and Serbian forces join their attacks against Michael, who sends his forces into [[Macedonia (Greece)|Macedonia]] and marches on to [[Thessaloniki|Thessalonica]]. In response, Michael is attacked – on the west coast of Epirus – by [[Manfred of Sicily]]. Manfred first occupies the major [[Ionian Islands]], including [[Corfu]]. Then he lands on the Albanian coast and takes [[Durrës|Durazzo]], [[Berat]], [[Vlorë|Valona]] and their environs.<ref>Fine, John Van Antwerp (1994). ''The Late Medieval Balkans: A Critical Survey from the Late Twelfth Century to the Ottoman Conquest'', pp. 160–161. Ann Arbor, Michigan: University of Michigan Press. {{ISBN|0-472-08260-4}}.</ref>
* The pagan [[Karelia (historical province of Finland)|Karelians]] start a destructive expedition to [[Sweden]] in which King [[Valdemar, King of Sweden|Valdemar]] requests Alexander IV to declare a crusade against them. This leads to the [[Third Swedish Crusade]] to [[Finland]] ([[1293]]–[[1295|95]]).

==== British Isles ====
* [[Battle of Cadfan]]: An English expeditionary army under [[Stephen Bauzan]] is ambushed and defeated by Welsh forces. The English are decimated by devastating guerilla attacks and the Welsh capture the English supply train. Stephen Bauzan is killed along with some 1,000–3,000 of his men. The remaining English flee the battle, Prince [[Llywelyn ap Gruffudd]] is said to have been present at the battle, collecting spoils from the fallen English army. According to sources, it is one of the greatest victories of a Welsh army in the field against a much more powerful English force.<ref>{{Cite web |title=Welsh Battlefields |access-date=2009-04-13 |url=http://www.welshbattlefields.org.uk/eng/?page_is=18 |archive-date=September 18, 2023|archive-url=https://web.archive.org/web/20230918044336/http://www.welshbattlefields.org.uk/eng/?page_is=18 |url-status=dead }}</ref>
* King [[Henry III of England]] relents to the demands of his son [[Edward I of England|The Lord Edward]] for assistance to fight the Welsh, originally made in [[1256]]). He joins him on a campaign to retake the territories lost to the Welsh forces led by Llywelyn ap Gruffudd.
* Henry III of England orders the production of a pure [[gold penny]] coin with a value of twenty pence. Unfortunately, the [[bullion]] value of the coins is about 20% higher than the nominal face value, leading to poor circulation, as coins are melted down by individuals for their gold content.
* [[Battle of Creadran Cille]]: Norman invading forces under [[Maurice FitzGerald, 2nd Lord of Offaly|Maurice FitzGerald]] are driven out by [[Gofraid O'Donnell]] in northern [[Connacht]] (Ireland). On [[May 20]], FitzGerald is killed in personal combat by O'Donnell.<ref>Chisholm, Hugh, ed. (1911). ''O'Donnell – Encyclopædia Britannica'', pp. 6–8. Vol 20 (11th ed.). Cambridge University Press.</ref>

==== Levant ====
* [[Venetian–Genoese Wars]]: The Venetian fleet under Admiral [[Lorenzo Tiepolo]] breaks through the harbour chain at [[Acre, Israel|Acre]] and destroys several Genoese ships. He also attacks the fortifications but Tiepolo is unable to expel the Genoese garrison (some 800 men strong and armed with 50–60 [[ballista]]e), from their quarter of the city throwing up a blockade.<ref name=Runciman3>[[Steven Runciman]] (1952). ''A History of The Crusades. Vol III: Kingdom of Acre'', pp. 238, 252. {{ISBN|978-0-241-29877-0}}.</ref>
* [[April 10]] &ndash; [[Aybak|Izz al-Din Aybak]], Mamluk sultan of [[Egypt in the Middle Ages|Egypt]], is murdered on orders of his wife, [[Shajar al-Durr]]. He is succeeded by his 14-year-old son, [[Al-Mansur Ali|Nur al-Din Ali]], as ruler of the [[Mamluk Sultanate]] (until [[1259]]).

==== Mongol Empire ====
* Spring &ndash; Mongol forces under [[Uriyangkhadai]] conduct a campaign against local [[Yi people|Yi and Lolo tribes]] in [[Vietnam]]. He returns to [[Gansu]] and sends messengers to the court of [[Möngke Khan]] informing him that [[Yunnan]] is firmly under Mongolian control. Möngke Khan honors and rewards Uriyangkhadai for his military achievements.<ref>Rossabi, Morris (2009). ''Khubilai Khan: His Life and Times'', pp. 24–27. University of California Press. {{ISBN|978-0-520-26132-7}}.</ref>
* Winter &ndash; Mongol forces move down from their base at [[Hamadan]], while [[Baiju Noyan]] crosses the river [[Tigris]] at [[Mosul]] with his army. On the left-wing [[Kitbuqa]] enters the plain of [[Iraq]], while Mongol forces under [[Hulagu Khan]] advance through [[Kermanshah]].<ref name=Runciman3/>

==== Asia ====
* March &ndash; The Japanese [[Kōgen]] era ends and the [[Shōka (era)|Shōka]] begins during the reign of the 14-year-old [[Emperor Go-Fukakusa]] (until 1259).

=== By topic ===

==== City and Towns ====
* [[June 5]] &ndash; The city of [[Kraków]] is granted [[Magdeburg rights]] by High Duke [[Bolesław V the Chaste]], having been rebuilt after being nearly destroyed during the [[First Mongol invasion of Poland]].

==== Education ====
* Louis IX of France ("the Saint") confirms the foundation by his chaplain [[Robert de Sorbon]] of the [[College of Sorbonne]] in [[Paris]], giving a formal college (and still-common name) to the already existing [[University of Paris]].<ref>{{cite web|url=http://www.sorbonne.fr/la-sorbonne/histoire-de-la-sorbonne/la-fondation-de-la-sorbonne-au-moyen-age-par-le-theologien-robert-de-sorbon/|title=La fondation de la Sorbonne au Moyen Âge par le théologien Robert de Sorbon|publisher=La Chancellerie des Universités de Paris|accessdate=2021-03-04}}</ref>

==== Literature ====
* [[Matthew Paris]], English monk and chronicler, personally interviews Henry III for an entire week while compiling his major work of English history, ''[[Chronica Majora]]''.

==== Natural Disaster ====
* [[1257 Samalas eruption|Samalas eruption]]: Mount Samalas volcano erupts on [[Lombok Island]], [[Indonesia]]. One of the [[List of volcanic eruptions by death toll|largest volcanic eruptions]] in the past 10,000 years, it creates severe climatic changes across the globe, leading to severe [[famine]] and death, and to one of the biggest geopolitical changes across the globe over the next few centuries.<ref>{{cite news|url=https://www.bbc.co.uk/news/science-environment-24332239|title=Mystery 13th Century eruption traced to Lombok, Indonesia|first=Jonathan|last=Amos|work=BBC News|publisher=BBC|date=2013-09-30|access-date=2013-09-30}}</ref><ref>{{cite news|url=https://www.theguardian.com/uk/2012/aug/05/medieval-volcano-disaster-london-graves|title=Mass grave in London reveals how volcano caused global catastrophe|first=Dalya|last=Alberge|date=2012-08-04|work=[[The Guardian]]|location=London}}</ref></onlyinclude>