I love the idea. You get a Viking-esque character, but with a bit of a different take as opposed to the typical beserker warrior.
By 5th level, your character will have a ton of experience under their belt; a rogue like that could find themselves almost anywhere, I would imagine. There's a lot of room to role play some background, create a personality, etc.
Keep in mind that your character will absolutely be viewed as a barbarian by the "civilized" folk of the five kindgoms - Vidirak, much like their Viking inspiration, are known to raid, pillage, etc. Northern Ertain won't be as unfriendly as a coastal area, but that predjudice will still be there.