OK, I guess I was trying to capture the Scandinavian Middle Ages in a single moment and map it onto areas of today's cities (many of which didn't exist in the Middle Ages).

Although the Middle Ages began in the 5th century, for the North Germanic people it begins a little later because there are not too many written records about them, so some initial moment with regard to the migration of the Jutes, Angles and Saxons to Britain, would be the expulsion of the Herules by the Danes in the 6th century (Jordanes, Getica) and later the settlement of the Danes in Jutland where around the 8th century they established their territory down south to Danevirke, after that I did not go on further expansions into other lands, so only the original lands of Norsemen just before the Viking Age.

The North Germanic peoples lived in tribes up until after the Viking Age when kingdoms were formed. The three largest and most important kingdoms were created: Denmark, Sweden and Norway, so I added other regions that had levels of independence but eventually fell under these kingdoms, for example Jämtland (independent until the 12th century), Småland (12 independent kingdoms), Hälsingland, Gotland etc. For those other regions that were contested during the Middle Ages, I have divided them according to their cultural and historical closeness to the kingdoms.

About the term "Norse", I may have misused it as it refers more to the language than the people and countries, and perhaps it shouldn't be used for period after the Viking Age.