Aalborg was founded, It was mentioned in 1075 by Adam of Bremen as a large town, the early name Alabur was written on one of Harthacnuts coins from 1040.
Oslo was founded.
Olaf Tryggvason sailed with a fleet to Venden. He was not unaware of the Danish-Swedish attack plan and he probably sailed for help from his friend Duke Boleslaw of Poland. Svein Forkbeard, Olof Skotkonung and the sons of Earl Haakon suddenly attacked the Norwegian fleet and Olaf Tryggvason was on 9th september killed at Battle of Svolder. The Norwegians suffered a devastating defeat and Sweyn Forkbeard was now in control of Norway.
The sons of Earl Haakon were given large land areas, but the Swedish king only got a smaller coastal area around Gøta river.
Leif "The happy" Eriksson sailed on a expedition to explore Vinland, 15 years earlier Bjarni Herlofsson was blown out of course and he discovered land and followed the coast. Vikings made a settlement at L ànse aux Meadows and traveled further in North America
Altinget in Iceland decided to install Christianity. To Iceland he sent the baptized Icelander Stefner Thorgilsson and the German priest Thangbrand, who quickly became unpopular but some Icelander turned christians Njal the wise and his sons and Hjalte Skeggeson became leader of the Christians. It nearly came to a battle at the Althing, but it was decided that the lawmaker Thorgejr should judge the case, he was heathen but made a compromise and decided that Christianity should rule Iceland and that all people that made public sacrifies should be expelled, but you could still eat horsemeat and pray to the old gods and lay small children to the wolves.
Island of ManÆthelred the unreadys fleet attacked Man in reprisal for viking raids.