854

Events

Emperor Lothair I meets his (half) brothers (Louis the German and Charles the Bald) in Attigny, Ardennes for the third time, to continue the system of "con-fraternal government".
Viking chieftains Rorik and Godfrid Haraldsson return to Denmark, to gain power after the death of King Horik I. During a civil war, they are forced to go back to Friesland.<ref>Norsemen in the Low Countries: Extracts from the Annales Bertiniani, 855 entry Template:Webarchive</ref>
The German city of Ulm is first mentioned, in a document by Louis the German.<ref>Zeit.de: Das Alter der Städte</ref>
Croatian–Bulgarian battle: Bulgarian Khan (later Knyaz) Boris I,<ref>{{#invoke:citation/CS1|citation

|CitationClass=web }}</ref> attacks the Duchy of Littoral Croatia, ruled by Duke Trpimir I during the First Croatian-Bulgarian War. It is fought on the Croatian territory in the vicinity of the Croatian–Bulgarian border<ref>Template:Cite book</ref> in present-day northeastern Bosnia and Herzegovina. None of the warring sides emerges victorious, Bulgarian forces retreat and finally both parties subsequently conclude a peace treaty.<ref>Template:Cite book</ref>

King Æthelwulf of Wessex sends his two youngest sons, Alfred and Æthelred, on a pilgrimage to Rome.<ref name=asc853>ASC 854 - English translation at Project Gutenberg</ref>
King Æthelweard of East Anglia dies, and is succeeded by his 14-year-old son Edmund ("the Martyr").<ref>Kirby, The Earliest English Kings, p. 161.</ref>
King Cyngen of Powys makes the first pilgrimage to Rome of a Welsh ruler.
Viking chieftain Ubba winters in Milford Haven (Wales) with 23 ships.<ref>Milford Haven Town Council website History, Chronology of Events Template:Webarchive</ref>