Ironic, isn't it? The way "the men from the north" fought for ruling over the romanized celts, the romano-britons of which King Arthur (or historicaly Artorius or something similar) was the most romantic example.
First, came the Angles, Saxons and Jutes, from a region just south of present-day Denmark. Then, it was the turn of the norwegians, but after doing only some raids (the one on the Lindisfarne monastery brought them postumuos celebrity), they were busy in Ireland, were they built among other cities, Dublin. The danes were the ones taking care of England. The 7 anglo-saxon kingdoms that existed in England, were all conquered, but one. The anglo-saxon king Alfred of Wessex was the only one to resist succesfully, and start the "reconquista" against the pagan danes. He is therefore, the only british king to be named "the great". Colonized danes coexisted with natives, to build together the nation that eventually will turn to be English.
Harald Hardrada had an interesting life. Of royal blood, he left his native Scandinavia to save his life. He earned fortune, fame and a good warband in Kiev and Nowgorod. The word "Russ" was the name of the vikings in the East, where they were also very busy. Harald returned home with his hardened followers, to fight for his rights. He gained both the crowns of Norway and Denmark, and planned to add the third, the one of England. It is a very inciting scenario to think of, if he had planned his invasion a couple of months later, or if William would have landed earlier, as he intended.
So, Harald Godwinson (son of Godwin, as per nordic languages) was defeated by the christian, sophisticated and french-ized scandinavians.

For more then 2 centuries, the vikings influenced history to a very large degree.