
According to BBC online, the Vikings did not terrify Europe and were actually peaceful settlers most of the time.
It becomes a story about not just conquest but immigration and assimilation. Many of the Vikings embraced Christianity. There was intermarriage. King Cnut, who became King of England and ruled for 25 years, replaced those at the top but allowed society to go on as before. At the same time they held on to Norse names and traditions. "My view is that there was a good deal of give and take," Townend says.
So, what were they? Terrible raiders who raped and pillaged? Or explorers and settlers? As always, history is frequently revised as more information is unearthed. This is a long article but worth reading for history buffs. It can be found @ BBC News - Were the Vikings really so bloodthirsty?