According to Erkka, it’s pseudomap of possible perception.. the North Sea on the map isn’t Arctic (although the Tribes live on that side) the sea is meant to be Gulf of Bothnia.
In my perception, I see it as Arctic in the north, and Scandinavian peninsula as an island (not visible), Gulf of Bothnia in the west and bay of Finland in the south. Then the placement of islanders and driik, also Tribes and Sartolaiset(with their knives: Bothnians) make more sense.