Hmm - I have been planning for a while a Vinland-related TL, and a good portion of what you wrote could fit right in perfectly. Well, except for some cultural issues - it
is a Battle of Svolder POD which also involves such things like Galicia-wank (Galicia as in the modern-day OTL region of Spain directly north of Portugal and the former Kingdom) and the berserkers finding their way to Vinland, with interesting results amongst the local Aboriginal people.

Or a TL which involves an Orthodox Christian Sweden and/or Finland (also with interesting results, such as the increased conservatism and/or archaism of either the standard Swedish language or the Eastern Swedish dialects).