In the Old Icelandic sources, its name is Burgundarholm, and Alfred the Great uses the form Burgenda land. Some scholars believe that the Burgundians are named after Bornholm; the Burgundians were a Germanic tribe which moved west when the western Roman Empire collapsed, and occupied and named Burgundy in France.

The island was originally part of Scania (Skåneland). When the eastern provinces of Denmark were ceded to Sweden in 1658, Bornholm was returned to Denmark-Norway two years later (along with Trøndelag and Anholt).

A immigration of Swedes, notably from Småland or Skåne, accured during the 19th century, seeking work and better conditions. Most Swedes left Bornholm later but some remained.


Bornholm, as a part of Denmark, was captured by Germany relatively early in the Second World War, and served as a lookout post and listening station during the war. The island's perfect central position in the Baltic Sea meant that it was an important "natural fortress" between Germany and Sweden, effectively keeping submarines and destroyers away from Nazi occupied waters. Several concrete coastal installations were built during the war, and several coastal batteries had tremendous range. However none of them were ever used and only a single test shot was fired during the occupation. These remnants of Nazi rule have since then fallen into disrepair and are mostly regarded today as historical curiosities. Many tourists visit the ruins each year, however, providing supplemental income to the tourist industry.

On 22 August 1943 a rocket (numbered V83, probably launched from a Heinkel He 111) crashed on Bornholm as part of a test - the warhead was a dummy made of concrete. This was photographed or sketched by the Danish Naval Officer-in-Charge on Bornholm, Lieutenant Commander Hasager Christiansen. This was the first sign British Intelligence saw of Germany's aspirations to develop flying bombs and rockets - which were to become known as V1 and V2.

Bornholm was heavily bombarded by Soviet forces in May 1945. Von Kamft, the German superior officer in charge of the island garrison refused to surrender to Soviet forces, as his orders were to surrender to the Allied Forces. The Germans sent several telegrams to Copenhagen requesting that at least one British soldier should be transferred to Bornholm, so that the Germans could surrender to the western allied forces instead of the Russians. When Von Kamft failed to provide a written capitulation as demanded by the Russian commanders, several Soviet aircraft relentlessly bombed and destroyed more than 800 civilian houses and seriously damaged roughly 3000 more during 7-8 May 1945. Eventually, the German garrison did surrender to the Soviet forces, which occupied the island until April 5, 1946.

More recently NATO radar installations have been placed on the island.

A Russian (Soviet) declaration after World War II stated that the placement of "foreign soldiers" (i.e., NATO forces) on Bornholm would be considered a declaration of war against Russia, and that Denmark should keep troops on it at all times to protect it from foreign aggression. This caused diplomatic problems at least twice: once when an American helicopter landed outside the city of Svaneke due to engine problems in a NATO exercise over the Baltic Sea, and once (sometime between 1999 and 2003) when the Danish government suggested shutting down Almegårdens Kaserne, the local military facility, since "the island could quickly be protected by troops from surrounding areas and has no strategic importance after the fall of the Iron Curtain".