In the map above, yellow represents Swedish Territory, green is areas given back to Denmark-Norway, and red is what was already Denmark-Norway. After Sweden (King Charles X Gustav) defeated Denmark-Norway (King Frederick III) in the Second Norther War, Danes residing in Sweden were exiled from there. Roskilde was the city Denmark-Norway was defeated in (in their own country). In this Treaty, Sweden received Danish territory (Scania, Blekinge, Halland, Bornholm, Bohulslän and Romsdal. Denmark was forced to end any anti-Sweden alliances. Denmark also was disallowed from passing any of their ships through the Baltic. This moment is important because it introduced the borders of Sweden, Denmark (and Norway) that exist today. It contributes to the political and social trajectory of the countries that exist today, but also provided borders that would separate and (attempt to) keep each out of the other.