Vikings is a term generously given to warriors, explorers and pirates among other trades and professions that were of Norse descent who were active from roughly 800 A.D to 1100 A.D. Venturing out and settling in various other parts of the world, they are known for many number of things, some true but others misconceptions, but their collective traits have made them iconic and popular to use often in fiction. As such they often appear in various different publishers comics to large and small degree.
The comic book series Northlanders from Vertigo comics features many Viking characters and themes. Although not strictly a Viking himself, Thor comics from Marvel do tend to delve into Viking subjects and characters as Thor was worshiped by many Vikings. Viking characters that have appeared in his books, include Harald Jaekelsson, Einar Thorvaldsdottir and Sigrid the Viking. Eric Northman from the True Blood comics, was also a viking prince, before he was turned into a vampire.
Major Story Arcs
Vikings from 1003 A.D have invaded New York city, led by vicious and powerful Lord Harald Jaekelsson. They had been cursed in their own time by a lone survivor of a village they had brutally slain and destroyed the inhabitants of. The man attempted to use dangerous rune magic to curse them, however he was shot with an arrow during the process and his blood washed over the artifact he was using, dramatically increasing its power and curse. As a result these vikings led by Harald Jaekelsson would sail for a 1000 years before reaching their goal and they would then be virtually invulnerable. Casually killing many humans, Thor and Doctor Strange are initially unable to defeat these cursed vikings, so they use magic to find descendants of the man who cast the original spell, as they may be of use. They find Sigrid, Magnus of the Danes and Erik Loonroth and with that they manage to make way against the cursed vikings, and Thor himself finally manages to defeat their leader Harald.