Editing 864 (section)

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

==== Europe ====
* Spring &ndash; Emperor [[Louis II of Italy|Louis II]] ('''the Younger''') marches with a [[Francia|Frankish]] army against [[Rome]]. While en route to the [[Pope|papal]] city, he becomes ill, and decides to make peace with [[Pope Nicholas I]].
* [[July 25]] &ndash; [[Edict of Pistres]]: King [[Charles the Bald]] orders defensive measures against the [[Vikings]]. He creates a large force of [[cavalry]], which inspires the beginning of French [[chivalry]].
* Viking raiders, led by [[Olaf the White]], arrive in [[Kingdom of Scotland|Scotland]] from the Viking settlement of [[Dublin]] ([[Ireland]]). He rampages the country, until his defeat in battle by King [[Causantín mac Cináeda|Constantine I]].
* [[Robert the Strong]], margrave of [[Neustria]], attacks the [[Loire]] Vikings in a successful campaign. Other Viking raiders [[Looting|plunder]] the cities of [[Limoges]] and [[Clermont-d'Excideuil|Clermont]], in [[Aquitaine]].
* King [[Louis the German]] invades [[Great Moravia|Moravia]], crossing the [[Danube|Danube River]] to [[Siege|besiege]] the ''civitas Dowina'' (identified, although not unanimously, with [[Devín Castle]] in [[Slovakia]]).<ref>{{cite book |last1=Bowlus |first1=Charles R. |title=Franks, Moravians, and Magyars: The Struggle for the Middle Danube, 788-907 |date=1995 |publisher=University of Pennsylvania Press, Incorporated |isbn=978-0-8122-3276-9 |edition=Illustrated |url=https://books.google.com/books?id=VZhnAAAAMAAJ|page=140}}</ref><ref>{{cite book |last1=Goldberg |first1=Eric Joseph |title=Struggle for Empire: Kingship and Conflict Under Louis the German, 817-876 |date=2006 |publisher=Cornell University Press |isbn=978-0-8014-3890-5 |edition=Illustrated, reprint |url=https://books.google.com/books?id=oyiTg0wgl58C |page=273}}</ref>
* [[Pepin II of Aquitaine|Pepin II]] joins the Vikings in an attack on [[Toulouse]]. He is captured while besieging the Frankish city. Pepin is deposed as king of [[Duchy of Aquitaine|Aquitaine]], and imprisoned in [[Senlis]].
* [[September 13]] &ndash; [[Pietro Tradonico]] dies after a 28-year reign. He is succeeded by [[Orso I Participazio]], who becomes [[Doge (title)|doge]] of [[Republic of Venice|Venice]].
* King [[Alfonso III of Asturias|Alfonso III]] conquers [[Porto]] from the [[Emirate of Cordoba]]. This is the end of the direct Muslim domination of the [[Douro]] region.<ref>{{cite book|last=Picard|first=Christophe|title=Le Portugal musulman (VIIIe-XIIIe siècle0. L'Occident d'al-Andalus sous domination islamique|year=2000|publisher=Maisonneuve & Larose|location=Paris|isbn=2-7068-1398-9|page=109}}</ref>

==== Asia ====
* [[Mount Fuji]], located on [[Honshu|Honshu Island]], erupts for 10 days, in an event known as the [[Historic eruptions of Mount Fuji#Jōgan eruption|Jōgan eruption]] ([[Japan]]).
* [[Hasan ibn Zayd]] establishes the [[Alid dynasties of northern Iran|Zaydid Dynasty]], and is recognized as ruler of [[Tabaristan]] ([[Northern Iran]]).<ref>{{cite journal |last1=Buhl |first1=Fr.|editor1-last=Bearman |editor1-first=P. |editor2-last=Bianquis |editor2-first=Th. |editor3-last=Bosworth |editor3-first=C. E. |editor4-last=van Donzel |editor4-first=E. |editor5-last=Heinrichs |editor5-first=W. P. |title=al-Ḥasan b. Zayd b. Muḥammad|journal=The Encyclopaedia of Islam|url=https://referenceworks.brillonline.com/entries/encyclopaedia-of-islam-2/al-hasan-b-zayd-b-muhammad-SIM_2758|edition=2nd|page=245|date=1986|publisher=Brill|url-access=subscription }}</ref>

=== By topic ===
==== Religion ====
* The [[Christianization of Bulgaria]] begins: [[Boris I of Bulgaria|Boris I]], ruler (''[[Knyaz (title)|Knyaz]]'') of the [[First Bulgarian Empire|Bulgarian Empire]], is converted to [[Eastern Orthodox Church|Orthodox Christianity]]. His family and high-ranking dignitaries accept the Orthodox faith at the capital, [[Pliska]] - from this point onwards the rulers of the Bulgarian Empire are known as ‘[[Bulgarian tsar|Tsars]]’ rather than ‘[[Khan (title)|Khans]]’.<ref>{{cite web|url=http://promacedonia.org/vz1b/vz1b_3_2.html|title=V. Zlatarski - Istorija 1 B - 3.2|first=Vassil|last=Karloukovski|date=1927|website=Promacedonia.org|access-date=August 26, 2017}}</ref>
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