Over the course of several days in early October 1710, Swedish and Danish warships clashed in a battle in Køge Bay, just south of Copenhagen. In the skirmishes known as the Battle of Køge Bay, the Danish warship Dannebroge sank.

The Dannebroge was launched at Nyholm’s Shipyard in October 1692 and was built under the auspices of the Danish admiral Henrik Span. The ship was equipped with more than 80 cannons, most of them in bronze. The ship was named after a Danish order of merit, the Dannebroge Order, which had been established by King Kristian V in 1671.

At first, the Dannebroge was the pride of the Danish navy. But as the fleet was expanded with an increasing number of newly built vessels, it began to take on a more modest role. Prior to the battle in Køge Bay, she was a line ship among many others.

On the morning of 4 October the Danish fleet was anchored just inside Køge Bay, awaiting a large number of carrier vessels that were sending Russian troops to Zealand in Denmark. But when the Swedish vessels approached the bay, the Danes first believed that it was the expected carrier fleet that had arrived. When they realised their mistake, a flurry of activity erupted on the Danish ships. The Dannebroge, which was anchored closest to the approaching Swedish ships, commenced the battle. But when Dannebroge’s cannons began firing, the ship was ignited by sparks that flared up when the cannons were fired. After nearly two hours, the fire reached the gunpowder storage area and the ship blew up. Almost the entire crew perished, and only nine people were rescued.

Salvage operations from the wreckage started as early as 1714. But because the ship was ravaged heavily by the fire and ensuing explosion, almost all the cannons were destroyed. However, about 10 tonnes of bronze pieces were salvaged which later came to be used in the manufacture of new cannons. Salvage operations also took place in the 1870s. The wreck was rediscovered in 1978, and a study was conducted resulting in a sketch of the wreck’s remains from the once-proud warship.