850 London and Cantebury was sacked

Peter Nicolai Arbo
Low countries:
In Friesland Harald Klak died and his brother Rurik became ruler. Rurik ruled Friesland, Dorestad and the Rhine area. While Harald Klak had defended the area, the situation changed. Rurik used Friesland as a base where future viking raids took place. Rurik captured Utrecht and kept the town for 70 year
Rurik sent 350 ships to England. The attackers captured the island Thanet, Kent and pillaged and looted the surrounding area. London and Canterbury was stormed and plundered. Vikings wintered for the first time in England. The first overwintering was on the Isle of Thanet in Kent
The king of  North Brega launched a rebellion against the Irish high king and he was supported by a band of vikings. The Danes defeated the Norwegians in a battle at Carlingford.
Island of Man 
The island of Man was settled by vikings.
Welsh Annals told that Cyngen died on the swords of "the Heathen," supposedly meaning viking raiders. The southern Welsh districts of Gwent, Glamorgan and Dyfedd was raided several times for twenty years by vikings.
The Frankish empire also had viking raids as the war between the sons of Louis the pious continued.
Ansgar created the first church in Hedeby and a second in Ribe. The church was build of wood on specific areas given by king Horik. Earl Howi and the citizens of Hedeby complained about the church bells and ringing church bells became forbidden.
Odense, Denmark
During archaeological excavations of the Viking castle at Nonnebakken, Odense led by Mads Runge, in 2015 a special item was found: a Viking Valkyrie riding a horse Jewelry dated to 850 AD
Viking Valkyrie riding a horse Jewelry(© Odense Bys Museer)