So the vikings did not just stop, but rather became crusaders:
"In 1107, Sigurd I of Norway sailed for the eastern Mediterranean with Norwegian crusaders to fight for the newly established Kingdom of Jerusalem; the kings of Denmark and Sweden participated actively in the Baltic Crusades of the 12th and 13th centuries"
https://en.wikipedia.org/wiki/Vikings
(But otherwise of course many factors contributed to the rise and fall of the vikings and there indeed seems to have been a niche, with a temporary weakness, no christian nordic fleets etc.)
How are civilized and baptized comparable concepts? The vikings surely had a civilization before christianity took hold and ascribing sone kind of higher ethics to christianity is also quite a stretch.
And like the other commenter pointed out, civilization is ill defined. I was mainly using it here from the christian point of view, where pagans are not civilized by definition. Not that the norse had not a complex society themself.
[0] https://www.amazon.com/Long-Ships-Review-Books-Classics/dp/1...