Treaty of Copenhagen (1660)

The Treaty of Copenhagen (Danish: Freden i København, Swedish: Freden i Köpenhamn) was signed on 27 May 1660, and marked the conclusion of the Second Northern War between the Swedish Empire and the alliance of Denmark-Norway and the Polish–Lithuanian Commonwealth. This treaty was a smaller follow-up treaty to that of the Treaty of Roskilde, which decisively delineated the mutually recognized boundaries of Denmark, Sweden, and Norway; boundaries which are almost exactly the same to this day.

Source: Wikipedia — Treaty of Copenhagen (1660) (CC BY-SA 4.0)