May have been a Teutonic from the Northern Crusades.
I think that more likely than my returning Varangian theory.
That may well be, but my point was they didn't find (or do not mention if they found) evidence of him being a Crusader. Lots of other folks were at war with each other at that time in Europe without being Crusaders.
It is unlikely he was a Teutonic Knight. The Teutonic Knights had no reason to venture to Finland. It is a tiny bit more possible it was a knight of the Livonian Swordbrothers - which eventually became part of the Teutonic Order.
The most likely thing is that it wasn’t a crusader at all - since no convincing evidence is produced that he was a crusader - and that he was Finish or Swedish.
The crusades in Finland, if they can even be called that (some doubt they happened) were by the Swedes.
Ironically there are more Teutonic Knights in Finland now than 800 years ago: https://www.facebook.com/TeutonicOrderCommanderyofFinland/