Originally posted by Lost Latios:

That sounds...awfully out of style. There is no evidence suggesting they ever used crossbows. I mean if they want to add them fine. Just seems strange to me is all.

Same can be said about using huge stonesblocks for building, horns in helmets, not to mention the plathora of magical weapons, potions, armor etc.
This is a viking inspired Fantasy game, with a huge emphasis on fantasy. :D