Battle of Copenhagen, an engagement during the Napoleonic Wars that occurred August 15–September 7, 1807. Fearful that Napoleon Bonaparte’s defeat of Russia and Prussia might lead to French control of Baltic fleets, Britain acted decisively to neutralize the substantial Danish navy, which was allied by treaty with Napoleon. The Danish fleet surrendered to Britain after Copenhagen was bombarded.
In early 1807, British leaders suspected that Napoleon might gain control of the Russian fleet and then perhaps the Danish and Swedish ones, too—together a strong enough force to pose a new threat to Britain’s naval mastery. Britain also had valuable trading interests in the Baltic, which was a vital source of naval supplies, including shipbuilding timber.
Britain prepared a large expedition—29,000 troops and more than 400 warships and transports—and remarkably managed to keep its destination secret, evading a large Danish force positioned in Jutland. The British expedition reached Denmark in early August 1807 and demanded that the Danes allow their fleet to be taken into British control. The Danes refused, and hostilities began.
British troops under Arthur Wellesley (later the Duke of Wellington) landed near Copenhagen and surrounded the city and its 13,000–14,000 defenders, of whom 7,500 were regular troops augmented by local Zealand militias. When further negotiations failed, the British fleet, under Admiral James Gambier, began a fierce bombardment on September 2, making much use of Congreve rockets (one of the first times rockets had been employed in European warfare). Soon much of the city was in flames, and the Danes, suffering heavy civilian casualties, were forced to surrender on September 7. The British left with 64 Danish ships and quantities of naval supplies, having burned and sunk an additional 14 Danish vessels.
Britain and Denmark remained at war for more than six years. Danish privateers did manage to capture some British merchant ships, and Britain had to convoy and escort its Baltic trade. There were a few minor clashes at sea but no further land battles.
Losses: Danish, 2,000–3,000 dead, 64 ships captured; British, 200 dead or wounded.