As the title says. How far can they advance their ships and grow the population by themselves? How plausible would it be to establish more contact with the Western and mediterranean civilizations?
Pre-Migration Era? Hmm.
You’ll want to expand the definition/sphere of influence of Scandinavia as its OTL territory is not the greatest. A South Germanic-screw could work, where the peoples of Scandza expand into OTL Germany during the Roman era but maintain some cultural unity with their northern brethren. Maybe they ally with Rome or Roman successors against the Germans? Dunno how plausible that would be.
Ideally, “Scandinavia” could include much of Germany, the northern Continental coast, and Britain.
Highly unlikely. You will need Greek colonies in the area that will boost tech-culture in the area. Maybe Pytheas of Massalia trip to the area had bigger impact and thus a colonial wave there? You can check my Massalia ATL(check from thread:278 BC. The North expedition.) Is pretty close to what you ask.
Wasn't most of Scandinavia still Uralic at that point in time?
It has been claimed that some of the oldest place-names in Scania are Uralic.At least everything north of Uppsala, although we aren't sure how much cross-cultural habitation occurred between the Proto-Norse and the various Uralic tribes even as far south as Växjö.
Wasn't most of Scandinavia still Uralic at that point in time?