The vikings got a bit of a bad reputation, probably in large part because they were not too popular amongst munks in England (who were avid writers). Sure, there was raping and plundering, but not necessarily so much worse than other peoples, and there was also trade and coexistence. We had particularly close relations to Scotland, and England is hardly in the position to accuse anyone else of plundering! ;)
Fun fact about the word viking: It literally means someone from a "vik", which is contemporary Norwegian for a cove. More traditionally, it's a dwelling by the coast, which explains the many -wich-towns in northern UK: The vikings would settle, usually for salt supplies, and name the place something ending with -vik.
So a Viking is not a job description as much as someone dwelling by the sea!