More recently (just months ago) a cut stone foundation for a more permanent dwelling was found in Southern Norway and identified as ............ well, fur shur, something far older than Norse ~ but they weren't quite ready to match that up with the known Sa'ami artifacts found in the same region.
So, nothing firm on that yet, but even Alaska is turning up foundations and artifacts more typical of NE Asia, but older!
The North was warmer in the past.
Yes it was, and multiple times; someone I know online stated that according to records, his Scandinavian ancestors traded with eastern Asia by sailing to and from the Bering Strait in the Arctic Ocean during the long summers of the medieval warming period.