Bornholm (; Old Norse: Burgundaholmr, "the island of the Burgundians") is a Danish island in the Baltic Sea, to the east of most of Denmark, south of Sweden, and north of Poland. The main industries on the island include fishing, arts and crafts such as glass making and pottery using locally worked clay, and dairy farming. Tourism is important during the summer. The topography of the island consists of dramatic rock formations in the north (unlike the rest of Denmark which is very flat) sloping down towards pine and deciduous forests (greatly damaged by storms in the 1950s) and farmland in the middle and sandy beaches in the south.
Bornholm Regional Municipality covers the entire island. Bornholm was one of the three last Danish municipalities not belonging to a county— the others were Copenhagen and Frederiksberg. On 1 January 2007, the municipality lost its short-lived (2003 to 2006) county status and became part of Region Hovedstaden (the Copenhagen Capital Region).
Strategically located in the Baltic Sea, Bornholm has been fought over for centuries. It has usually been ruled by Denmark, but also by Lübeck and Sweden. The Hammershus castle ruin, at the northwestern tip of the island, is the largest medieval fortress in northern Europe, testament to the importance of its location.
In Old Norse the island was known as Borgundarholm, and in ancient Danish especially the island's name was Borghand or Borghund; these names were related to Old Norse borg "height" and bjarg/berg "mountain, rock", as it is an island that rises high from the sea. Other names known for the island include Burgendaland (9th century), Hulmo / Holmus (Adam of Bremen), Burgundehulm (1145), and Borghandæholm (14th century). 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.
Swedish forces conquered the island in 1645, but returned the island to Denmark in the following peace settlement. After the war in 1658, Denmark ceded the island to Sweden under the Treaty of Roskilde along with the rest of the Scanian provinces and Trøndelag, and it was occupied by Swedish forces.
A revolt broke out the same year, culminating in Villum Clausen's shooting of the Swedish commander Johan Printzensköld on 8 December 1658. Following the revolt, a deputation of islanders presented the island as a gift to King Frederick III on the condition that the island would never be ceded again. This status was confirmed in the Treaty of Copenhagen in 1660.
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, as it was a part of the Eastern Front. 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 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 V-1 flying bomb (numbered V83, probably launched from a Heinkel He 111) crashed on Bornholm during 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 V-1 and V-2.
Liberation by the Soviet Army and occupation 1945–1946
Bornholm was heavily bombarded by Soviet forces in May 1945. German garrison commander Gerhard von Kamptz refused to surrender to the Soviets, as his orders were to surrender to the Western Allies. 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 Kamptz failed to provide a written capitulation as demanded by the Soviet commanders, Soviet aircraft relentlessly bombed and destroyed more than 800 civilian houses in Rønne and Nexø and seriously damaged roughly 3,000 more on 7–8 May 1945.
During the Russian bombing of the two main towns on 7 and 8 May, Danish radio was not allowed to broadcast the news because it was thought it would spoil the liberation festivities in Denmark. On 9 May Soviet troops landed on the island, and after a short fight, the German garrison (about 12,000 strong) surrendered. Soviet forces left the island on 5 April 1946.
After the evacuation of their forces from Bornholm, the Soviets took the position that the stationing of foreign troops on Bornholm would be considered a declaration of war against the Soviet Union, and that Denmark should keep troops on it at all times to protect it from such foreign aggression. This policy remained in force after NATO was formed, and Denmark had joined it: the Soviets accepted the stationing of Danish troops, which were part of NATO but were far from that alliance's most powerful element, but strongly objected to the presence on the island of other NATO troops: particularly of US troops.
This caused diplomatic problems at least twice: once when an American helicopter landed outside the town of Svaneke due to engine problems in a NATO exercise over the Baltic Sea, and once (circa 2000) when the Bornholms Værn (Bornholm Guard) was disbanded, becoming part of the Guard Hussars. The Danish government suggested shutting down Almegårds Kaserne, the local barracks, since "the island could quickly be protected by troops from surrounding areas and has no strategic importance after the fall of the Iron Curtain".