Battle of Køge Bay (1677)

The Battle of Køge Bay was a naval battle between Denmark and Sweden that took place in bay off Køge 1–2 July 1677 during the Scanian War. The battle was a major success for admiral Niels Juel and is regarded as the greatest naval victory in Danish naval history.

Prelude
After losing control of the Baltic Sea in the Battle of Öland the year before, the Swedish navy wanted it back. The Danish fleet, commanded by Niels Juel, had 1,354 cannons and 6,700 men, while the Swedish fleet, commanded by Henrik Horn, had +1,792 cannons and 9,200 men.

On 20 May, Sjöblad's squadron from Gothenburg had already left, before the rest of the fleet from Stockholm had set sail. This led to the catastrophic defeat at the battle of Möen where Sjöblad's squadron of two ships of the line, six armed merchant ships (classed as frigates) and a few smaller ships (ca 400 cannons in total) fought against the superior firepower of the Danish fleet, which had about: nine ships of the line, four frigates (ca 670 cannons). In the following battle, Sjöblad's own flagship Amarant was captured and the outcome destroyed the initial Swedish plan and eventually led to the future defeat at Koge Bay.

The remaining Swedish fleet had left Dalarö, near Stockholm, on 9 June 1677. On 13 June it was joined by Kalmar, off Öland, and by Andromeda and Gustavus, survivors of Sjöblad's squadron. The Danish fleet had left Copenhagen on 24 June 1677. Lack of wind forced it to anchor off Stevn's Point. At daybreak on 19 June the two fleets sighted each other.

The battle
At about 8am on 30 June, Horn weighed anchor with a SSW wind and sailed toward the Danish fleet, sending two ships to try to draw Juel out; he in turn sent two ships to attack them. Both sides kept their distance, the Swedes forming a line, followed by the Danes. Juel tried in vain all night to get the weather gauge.

On 1 July at daybreak, despite some of his ships having fallen behind, Juel closed, as did the Swedes, and fighting began at about 5am. Horn sent in fireships but the Danes towed them aside. As the fleets approached the coast near Stevn's Point, Juel bore away a little in the hope that the Swedes would try to stay to windward and run aground.

Indeed, the Swedish warship, Draken, ran aground and Horn had to leave ships behind to protect it as he turned 180 degrees. After the turn, the fleets sailed parallel to each other, but the Swedish fleet had made a gap in their line which Juel utilised to break through, thus isolating several major warships. This was the turning point of the battle, which soon turned into a complete rout.

The Swedes lost eight war ships, several smaller ships and about 3,000 men. The Danish fleet did not lose any ships, only damages on the ships and approximately 100 men were killed and 275 wounded.

Aftermath
This battle is recognized as Denmark-Norway's greatest naval victory, and according to 19th century Danish and Norwegian marine officers, Juel invented the "break-through" tactic, more than a hundred years before the British admiral George Rodney broke the French line in the Battle of the Saintes in the Caribbean sea 1782.

The defeat of the Swedish fleet also gave Denmark-Norway control of the Baltic sea, and thereby the inner supply lines of the Swedish Empire. Admiral Tromp's fleet was ordered to "burn and defile, plunder, kill or abduct the people", with the intention of luring Swedish troops away from Scania and thus relieve the land-bound operations. Although Öland and parts of the coast of Småland were devastated, king Charles XI didn't move any forces from main front in Scania. During the remainder of the war, Denmark completely dominated at sea, even after the Netherlands made peace with Sweden in 1678. The Swedish fleet avoided further confrontations and could no longer maintain the line of communication with Swedish Pomerania; the last Swedish troops, on Rügen capitulated to Brandenburg in December 1678.