May 27 In Nordic History

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  Swedish territories in 1658 (green marks territories ceded to Denmark-Norway.)

• May 27 In Nordic History
  1660: The Treaty of Copenhagen is signed, marking the conclusion of the Second Northern War between Sweden 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 declared the official boundaries of Denmark, Sweden and Norway—boundaries which are almost exactly the same to this day.