Editing 1278 (section)

==== Europe ====
* [[May 1]] &ndash; [[William of Villehardouin|William II of Villehardouin]], prince of [[Principality of Achaea|Achaea]], dies. By the terms of the [[Treaty of Viterbo]], his lands passed under the direct control of [[Charles I of Anjou|Charles I]], king of [[Kingdom of Sicily|Sicily]]. Charles appoints a ''[[bailiff]]'' to rule the Latin principality.<ref>Fine, John Van Antwerp (1987). ''The Late medieval Balkans: A Critical Survey from the Late Twelfth Century to the Ottoman Conquest'', p. 193. Ann Arbor, Michigan: University of Michigan Press. {{ISBN|0-472-08260-4}}.</ref> In response, Charles swears fealty to the new pope, [[Pope Nicholas III|Nicholas III]], on [[May 24]]. He promises not to attack or invade the [[Byzantine Empire]] because Nicholas has hopes to unify the [[Eastern Orthodox Church|Orthodox Church]] with the [[Catholic Church]].<ref>Fine, John Van Antwerp (1987). ''The Late medieval Balkans: A Critical Survey from the Late Twelfth Century to the Ottoman Conquest'', p. 186. Ann Arbor, Michigan: University of Michigan Press. {{ISBN|0-472-08260-4}}.</ref>
* [[August 5]] &ndash; [[Siege of Algeciras (1278–1279)|Siege of Algeciras]]: Castilian forces (some 30,000 men) led by King [[Alfonso X of Castile|Alfonso X]] ("the Wise") besiege [[Algeciras]] (at this time under control of the [[Marinid Sultanate|Marinids]]). A fleet of 24 ships and some 80 galleys is placed in the [[Bay of Gibraltar]] to prevent the supply of the city from nearby [[Gibraltar]]. The fleet is made up of most of the members of the [[Order of Saint Mary of Spain]], a military-[[religious order]] which is concentrated in naval warfare.<ref>Joseph F. O'Callaghan (2011). ''The Gibraltar Crusade: Castile and the Battle for the Strait'', p. 75. {{ISBN|978-0-8122-2302-6}}.</ref>
* [[August 26]] &ndash; [[Battle on the Marchfeld]]: German-Hungarian forces (some 9,000 men) led by Kings [[Rudolf I of Germany]] in alliance with [[Ladislaus IV of Hungary]] ("the Cuman"), defeat and kill [[Ottokar II of Bohemia|Ottokar II]], ruler of [[Kingdom of Bohemia|Bohemia]]. The battle ends the power struggle between Rudolf and Ottokar over the fate of [[Central Europe]]. Rudolf's [[House of Habsburg]] will continue to rule [[Austria]] and other captured territories, until the end of [[World War I]] in [[1918]].<ref>Clauss, M. (2010). Rogers, Clifford, J. (ed.). ''The Oxford Encyclopedia of Medieval Warfare and Military Technology: Volume I'', p. 552–554. Oxford: Oxford University Press. {{ISBN|978-0195334036}}.</ref>
* [[September 29]] &ndash; Aragonese forces led by King [[Peter III of Aragon|Peter III]] take the Muslim stronghold of [[Montesa, Valencia|Montesa]], putting an end to two years of [[Mudéjar]] rebellion. The defeated Muslims are expelled from the realm and go into exile.<ref name=negotiating>{{cite book|last=de Epalza|first=Miguel|title=Negotiating cultures: bilingual surrender treaties in Muslim-Crusader Spain under James the Conqueror|year=1999|publisher=Brill|isbn=90-04-11244-8|url=https://books.google.com/books?id=IjFacnscoBIC&q=Treaty+of+Alcaraz+1243|page=120}}</ref>