865 - The great Danish army

Lorents Frølich: Looting, plunder & arson
England
The great Danish army started the great viking raid which would lead to the control of northeast England. The vikings had for several years resided on the island Thanet and more and more vikings arrived. Reinforcements arrived under the leadership of the chieftains Halfdan the widefarer,Ubbe and Ivar the boneless (Sons of Ragnar Lothbrok) and after plundering and pillaging Kent the viking army moved to East Anglia where the great Danish army got horses and created a headquarter for the winter. The Angles now had to struggle for 14 years.
France
A viking army attacked Saint Denis, but was struck by an epidemic, maybe dysentery.
Scotland
Óláf Cuaran and Ivar Boneless, son of Ragnar Lothbrok, the rulers of  Dublin raided Strathclyde
Denmark
Ansgar died after being ill with a blood disease for several months on the 3. February 865, he was buried in Saint Peters cathedral ,Bremen and was later proclaimed a saint.
Rembert became the new archbishop of Bremen.
Dragonship from Tulstrup Skaane runestone

Bosporus
A Rus viking naval expedition force had for the first time threatened the Byzantines in Constantinople.