A part of Finnish history

Recently a map where cities of more than 500 people were placed on world map. Terminology aside, I was of course first checking out how Finland looks on this map.

Entire map here

And here is cropped Finland where I very very quickly copy pasted rough current country borders on top of it. Borders are skewed, badly placed and very likely of incorrect size but they are close enough to illustrate my point:

I noticed that for some reason, there is interesting clear divide inside the country, southwestern part of having cities (towns, whatever term you prefer) quite densely, and northeastern part of being very sparse. Hmm. Curious, wonder if there is an historical reason..

Although I was almost certain already, I did quick googling found this article, listing historical borders of Finland. Historically (granted, part of following is my opinion) Finland has been either wild frontier, part of Sweden on west or Novgorod (later Russia) on east, often having been divided up by these two powers. Frontier part being areas, inside or outside these countries allocated borders where their respective governments couldn't or wouldn't reach. Although due to climate, this frontier never was anything like later western frontier of USA, more like wilderness where people could just vanish to live their own life without having to bother with tax collectors, army recruiters and other nuisances of foreign government.

But I digress here. As I remembered, the density border I imagined in above picture matches very closely border agreed by Sweden and Novgorod in 1323, 'Pähkinäsaaren rauha' (as it is known in Finland, Treaty of Nöteborg more internationally). This border stayed in place for next centuries, and changed next time only in 1595 and then 1617.

While I am not familiar on how Sweden and Russia treated this land over this time, I can, based on above map make a guess where Sweden encouraged people moving out and forming communities, while Novgorod .. didn't, and as a result of this one historical border, the entire northeastern part of Finland still remains mostly empty land.

Maybe pointless, but I found this interesting nevertheless.