Basques and Irish would be my option if I were to reply on who are the 'good old Europeans', especially the Irish, as they have been the most isolated of all Europeans. Their ancestry has been traced back to tens of thousands of years in Europe. Other European groups like the Finns have had genetic admixture from a relatively fairly recent time. So the core of Europeaness would be the Westernmost Europeans (Irish, Basques, etc).
So the core of Europeaness would be the Westernmost Europeans (Irish, Basques, etc).
That's a pretty limited Europe you have. If you wanted to search for top three oldest Northeners, Irish would be an easy one for sure. Basque and some Saami would be an obvious ones aswell. Then I'd take the entire region between Scandia and the Urals and started skimming thru the Finnic folk, despite that some people you end up finding for may refer to themselves as Swedes or Russians nowadays.
Uralic is indeed a linguistic term. However, the fact that Finns, who are living several thousand chilometers west of Urals do speak a language that is related - even if very distantly - to languages spoken in that area is interesting. In order for a language to spread there must have been some kind of contact between people. Now, there actually is plenty of archeological evidence of contacts between people living in Finland with the people living in Urals.
And there is also archeological evidence in Ural region about contacts with Fennoscandia.
Yes, there were contacts between the Vikings, who used the rivers as their trading routes and various Finnic, Permian and Ugric populations living either directly by the rivers or however had contacts with people living near the rivers. However, the I'd say that the bronze age trade was even more extensive. Copper from the Urals was traded practically everywhere from Baikal to Baltics.
In sweden, we say "finpajsare är nordens blattar" which can be translated to "finns are the niggers of Nordic".
I dont really know in a racial way how connected they are to others country, but in a cultural way finns have strong relationship with Sweden. In the west-northern finland they have swedish as a mother-tounge and í think the population is quite mixed there and also along the whole west coast.