Battle of the Sound
The naval Battle of the Sound took place during the Second Northern War, near the Sound or Øresund, just north of the Danish capital, Copenhagen. Sweden had invaded Denmark and an army under Charles X of Sweden had Copenhagen itself under siege. The Dutch fleet was sent to prevent Sweden from gaining control of both sides of the Sound and thereby controlling access to the Baltic Sea as well as of its trade.

The Swedes lost five ships in the action compared to one Dutch ship, however, remaining allied ships were more damaged. Also, considering the slightly fewer losses of men in the Swedish army; 1,200 compared to 1,400 (439 killed, 269 captured and slightly more than 650 wounded allies), the battle is considered a tactical draw. Strategically, however, it was a major allied victory.