The Gunboat War (Danish: Kanonbådskrigen, Norwegian: Kanonbåtkrigen; 1807–1814) was the naval conflict between Denmark–Norway and the British Navy during the Napoleonic Wars. The war's name is derived from the Danish tactic of employing small gunboats against the conventional Royal Navy. In Scandinavia it is seen as the later stage of the English Wars, whose commencement is accounted as the First Battle of Copenhagen in 1801.
The naval conflict between Britain and Denmark commenced with the First Battle of Copenhagen in 1801 when Horatio Nelson's squadron of Admiral Parker's fleet attacked the Danish capital. This came as a basis of Denmark-Norway's policy of armed neutrality during the latter stages of the French Revolutionary Wars, where Denmark used its naval forces to protect trade flowing within, into and out of the Danish-Norwegian waters. Hostilities between Denmark-Norway and the United Kingdom broke out again by the Second Battle of Copenhagen in 1807, when the British attacked the Danish capital to ensure that the Danish-Norwegian fleet did not fall into the hands of Napoleon.
As a result of the British confiscation and destruction of large parts of the Danish-Norwegian fleet during the assault on Copenhagen, the Dano-Norwegian government decided to build gunboats in large numbers to compensate the loss. The gunboats were originally designed by a Swede, Fredrik Henrik af Chapman, and the strategic advantage of gunboats lay in the fact that they could be produced rapidly and inexpensively throughout the kingdom. The tactical advantages were that they were highly manoeuvrable, especially in still and shallow waters and presented small targets. On the other hand, the boats were vulnerable and likely to sink from a single hit. They therefore could not be used in rough seas, and they were less effective against large warships. Still, the Danish-Norwegian government produced more than 200 gunboats in two models: the shallop gunboat which had a crew of 76 men, with an 18- or 24-pounder cannon in the bow and another in the stern, and the smaller barge type that had a total crew of 24 men, armed with a single 24-pounder.
The Danish Commodore (later, Admiral) Steen Andersen Bille (1751–1833) is credited with being the driving force behind the post-1807 Dano-Norwegian strategy of gunboat warfare. Below  is a description of each of the four classes of gunboats according to Junior Lieutenant Hans Georg Garde, himself a commander of one of the larger types of gunboats.
Reserve crew who could not be accommodated on board were quartered in buildings on land or in the frigate Triton which was in ordinary. Battle-ready gunboats had their crews on board.
Defences on the Norwegian coast in 1808 are listed at Royal Dano-Norwegian Navy order of battle in Norway (1808). Ten schooner-rigged gunboats capable of operating in the rougher Norwegian Sea were built in Bergen and Trondheim in the years 1808 to 1811.
In the first three years of the Gunboat War, these boats were on several occasions able to capture cargo ships from the convoys and to defeat British naval brigs, though they were not strong enough to overcome larger frigates and ships of the line. The British had control of Danish waters during the whole of the 1807–1814 war, and when the season was suited to navigation they were regularly able to escort large merchant convoys out through the Sound and the Great Belt. Although the discussion below focuses on armed encounters involving an exchange of fire, one must keep in mind that the British also captured numerous Danish privateers without firing a shot, and conducted an economic war, regularly seizing merchant vessels as prizes. Further economic damage was done by raids on the smaller islands, many populated but undefended. British warships landed to replenish firewood and water supplies, and forcibly to buy, commandeer or simply take livestock to augment their provisions.
The war overlapped, in time, the Anglo-Russian War. As a result, the British expanded their trade embargo to Russian waters and the British navy conducted forays northwards into the Barents Sea. The navy conducted raids on Hasvik and Hammerfest and disrupted the Pomor trade, the Norwegian trade with Russia.
On 12 August 1807, even before the war had been declared, the British sixth-rate HMS Comus took part in a notable, illegal, and ultimately one-sided single-ship action when she captured the 32-gun Danish frigate (fregat) Friderichsværn. In the engagement the British suffered only one man wounded; the Danes lost 12 men while 20 were wounded, some mortally. Lloyd's List described the Danish vessel as a "Danish Frigate, of 32 Guns, late Guardship", and reported that the action, near Elsinor, had been short. The Royal Navy took Frederiksværn into service as HMS Frederickscoarn.
On 23 August, the British HMS Prometheus fired Congreve rockets from her decks against a Danish gunboat flotilla, but the attack had little effect. The British were instead more successful on 11 September when HMS Carrier brought to the British Admiralty the despatches from Admiral Thomas McNamara Russell announcing the capitulation of the small island of Heligoland to the British. Heligoland later also became a centre for smuggling and for espionage against Napoleon.
In the East Indies, troops from the 14th Regiment of Foot landed from HMS Russell on the Coromandel Coast on 13 February 1808 and took over the Danish possessions at Tranquebar. On 14 March, the 14-gun HMS Childers and the Danish 20-gun sloop HDMS Lougen engaged in an inconclusive single-ship action. Childers lost two men killed and nine wounded before she could escape and return to Leith. On 22 March the British ships of the line HMS Nassau and HMS Stately destroyed the last Danish ship of the line, HDMS Prinds Christian Frederik, commanded by Captain C.W. Jessen, in the Battle of Zealand Point. Nassau was herself a former Danish vessel. Nassau had one man killed and 16 men wounded, while Stately had four killed and 27 wounded. The Danes lost 55 men killed and 88 wounded.
Boats from HMS Daphne and HMS Tartarus, supported by the brig HMS Forward, drove ashore a Dano-Norwegian convoy at Flodstrand, near The Skaw on 22 April. The convoy was taking supplies for the relief of Norway as a result of food shortages that had occurred there after the British had begun their blockade between Denmark and Norway in 1807. The British went in under heavy fire from the shore and a castle there and brought out five brigs, three galliots, a schooner, and a sloop (totalling some 870 tons burthen), for the loss of five men wounded. The British frigate HMS Tartar also approached Bergen under Dutch colours on 15 May in order to attack the Dutch frigate Guelderland, which had been undergoing repairs there. Unfortunately for the British the Guelderland had already sailed, so during the night the British sent in boats in an attempt to attack other shipping in the harbour. When the boats came under heavy fire, Tartar came in to cover them, only to come under attack by the schooner Odin and five gunboats. During the Battle of Alvøen Tartar's captain and another seaman were killed and twelve men were wounded before Tartar was able to make her escape.
The hired armed cutter Swan found herself in action off the island of Bornholm with a Danish 8-gun cutter-rigged vessel on 24 May. Swan had been carrying despatches when she had spotted the Danish vessel and lured her out. The engagement ended with the Danish vessel exploding, while Swan suffered no casualties despite coming under fire both from the Danish vessel and the batteries on Bornholm. The fire from the batteries and the sighting of more Danish vessels forced Swan to withdraw after the battle without being able to make efforts to rescue survivors.
On 4 June four Danish gunboats attacked HMS Tickler and captured her after a four-hour fight. Tickler had lost her captain and 14 other men killed, and 22 other officers and men killed and wounded out of her crew of 50 men; the Danes had one man wounded. The Danes would later use Tickler as a cadet training ship.
The Danes were also victorious on 19 June, when the brig HMS Seagull pursued and caught up with the Danish brig HDMS Lougen, which was armed with eighteen short 18-pounder guns and two long 6-pounder guns. About 20 minutes into the engagement six Danish gunboats arrived from behind some rocks and in two divisions of three each took up positions on Seagull's quarter and fired on her with their 24-pounder guns while Lougen fired on her larboard bow. Within half an hour the Danish fire had badly damaged Seagull's rigging and dismounted five of her guns. Eventually Seagull struck, having lost eight men killed and 20 wounded, including her captain, R.B. Cathcart. Seagull sank soon after the Danes captured her, drowning several of her captors who were aboard. The Danes later recovered Seagull and added her to their navy.
Immobilized by a dead calm, HMS Africa, under Captain John Barrett, barely survived an attack by 25 Danish gunboats and seven armed launches under the command of Commodore J.C. Krieger in an action in the Øresund on 20 October 1808. Africa lost nine men killed and 51 wounded; had night not descended the Danes might well have captured her. The British, however, were less fortunate on 5 December, when the bomb vessel HMS Proselyte was wrecked on Anholt Reef while caught in the ice. The reason that the vessel sank in that area was because the Danes had closed the lighthouse on the island of Anholt, in the Kattegat early during the war, and the Admiralty had ordered her to station herself off the island on 9 November to carry a light for the safety of passing convoys. All her crew was however saved.
The British 64-gun third rate Standard, under Captain Aiskew Paffard Hollis, and the 18-pounder 36-gun frigate HMS Owen Glendower captured the island of Anholt on 18 May 1809. A party of seamen and marines under the command of Captain William Selby of Owen Glendower, with the assistance of Captain Edward Nicolls of the Standard's marines, landed. The Danish garrison of 170 men put up a sharp, but ineffectual resistance that killed one British marine and wounded two before the garrison then surrendered and the British took immediate possession of the island. The principal objective of the mission was to restore the lighthouse on Anholt to its pre-war state to facilitate the movement of British men of war and merchantmen navigating the dangerous seas there.
On 9 June a Danish and Norwegian flotilla of twenty-one gunboats and seven mortar boats attacked a British convoy of 70 merchant ships off the island of Saltholm in Øresund Strait near Copenhagen. The Dano-Norwegian flotilla was able to capture 12 or 13 merchant vessels, plus HMS Turbulent, one of the escorts. The Danes also captured HMS Allart during the Battle of Saltholm on 10 August. During the battle HMS Allart, a former Danish Navy brig, chased Lougen and Seagull into Fredriksvern only to find herself pursued by 15 Danish gunboats, arrayed in three divisions. After a three-hour chase the gunboats closed with Allart and an engagement began. After two hours Allart struck, having had her rigging shot away and having lost one man killed and three wounded. On 12 August, Commander John Willoughby Marshall and HMS Lynx were in the company of the gun-brig HMS Monkey, Lieutenant Thomas Fitzgerald, when they discovered three Danish luggers off the Danish coast. The water was too shallow for Lynx, so Marshall sent Monkey and boats from Lynx in to cut them out. The largest of the luggers, which had four guns and four howitzers, opened fire on Monkey before all three luggers ran ashore once Monkey and the launch's 18-pounder carronade returned fire. The British refloated the luggers and brought them out the next day, having taken no casualties. In their haste to quit the vessel, the Danes failed to fire the fuse on a cask of gunpowder they had left by the fireplace on the largest lugger. Marshall thought the Danes' behaviour in leaving the explosive device disgraceful. The Danish-Norwegian navy managed to capture another British vessel on 2 September, when a Danish gunboat flotilla from Fladstrand, North Jutland, under the command of Lieutenant Nicolai H. Tuxen, captured the gun-brig HMS Minx. The engagement cost Minx two dead and nine wounded. The British Royal Navy had stationed her off the Skaw Reef to show a warning light. HMS Sheldrake reported the loss to the Admiralty.
Early in 1810 the Danes ceased sending provisioning ships to Norway because of British naval activity in Øresund and withdrew the naval officers that were so involved to Zealand. Meanwhile, there were difficulties in transporting grain from the Vordingborg, in the south of Denmark, past Møn to Copenhagen. This was overcome by using gunboats to convoy the merchant vessels, as the gunboats were much more maneuverable in the shallow coastal waters, and restricting the cargo vessels to those which could pass inside of Møn. Larger seagoing ships which would have to go outside, i.e. east of Møn, were too liable to be caught by the British. These actions, together with a good form of coastal signalling, resulted in a steady supply of grain to the Danish capital.
On 13 April 1810, four Danish gunboats, under the command of First Lieutenant Peter Nicolay Skibsted, captured the British gunboat Grinder off the Djursland peninsula near Grenå. Grinder was armed with one 24-pounder gun and one 24-pounder carronade. She was under the command of Master's Mate Thomas Hester and had over-wintered at Anholt. Of her crew of 34 men, two were killed and two wounded in the action.
On 23 May, seven Danish gunboats engaged the Cruizer-class brig-sloop Raleigh, Alban, and His Majesty's hired armed cutter Princess of Wales, off the Skaw. The engagement cost the Danes the loss of one gunboat, which blew up, and heavy damage to the rest.
The Battle of Silda was fought on 23 July near the Norwegian island of Silda. The British frigates HMS Belvidera and HMS Nemesis attacked the pilot's station on the island and defeated the three gun schooners Odin, Tor and Balder and the gun barge Cort Adeler, which were stationed there.
On 12 September, six Danish gunboats captured a becalmed Alban after a four-hour battle during which she lost her captain and one man killed and three men wounded. The Danes then took her into service as The Alban.
Danish gunboats manned by nearly 1,000 men, including infantry forces attempted to recapture Anholt on 27 February 1811. The Battle of Anholt resulted in a Danish withdrawal to Jutland, with heavy losses. The Danes did however emerge victorious on 23 April when Swan encountered three Danish gunboats in Sunningesund. A shot from one of the gunboats damaged Swan and resulted in the wetting of her powder magazine, forcing her surrender. The Danes boarded her but were able to retrieve little before Swan sank off Uddevalla, on the Swedish coast north of Gothenburg. The fight cost Swan two men killed, as the same battle apparently also resulted in the damaging of the hired armed cutter Hero.[Note 1] On 11 May, Rifleman recaptured Alban from the Danes. The capture occurred after a 12-hour chase near Shetland. At the time of her capture Alban was armed with 12 guns and had a crew of 58 men, all under the command of a lieutenant of the Danish navy. She was three days out of Farsund in Norway and had taken no prizes.
On 31 July 1811, HMS Brev Drageren and Algerine were cruising together in Long Sound, Norway, when they encountered and engaged three Danish brigs: the 20-gun Langeland, the 18-gun Lügum, and the 16-gun Kiel. Outnumbered and outgunned, the British vessels took flight. The next day Brev Drageren unsuccessfully re-engaged first one and then two of the brigs. In the inconclusive engagement each British vessel sustained one man killed, and Brev Drageren also had three wounded. On 17 August HMS Manly sailed from Sheerness with a convoy for the Baltic. On 2 September, while she was cruising off Arendal on the Norwegian coast in the company of Chanticleer, three Danish 18-gun-brigs (Alsen, Lolland, and Samsø) engaged them. Lolland engaged Manly while the other two chased Chanticleer but she maintained a course away from the action and made good her escape. In the engagement with Lolland, Manly had her spars and rigging cut to pieces. With only six guns left, and having lost one man killed and three wounded, Manly was forced to strike.
The last major fight between Danish and British warships took place on 6 July 1812 during the Battle of Lyngør, when a small squadron of British warships met a small squadron of Danish warships at Lyngør on the Norwegian coast. The British withdrew after destroying the Danish frigate Najaden. On 2 August the same year, boats of HMS Horatio, which was under the command of Captain Lord George Stuart, captured two Danish vessels, under the command of Lieutenant Hans Buderhof, and their prize, an American vessel of about 400 tons burthen (bm). The two Danish vessels were schooner No. 114 (of six 6-pounders and 30 men), and cutter No. 97 (of four 6-pounders and 22 men). In the action the British lost nine men killed and 16 wounded, of whom two died of their wounds; the Danes lost ten men killed and 13 wounded.
As a result of the Swedish invasion of Holstein in December 1813 during the War of the Sixth Coalition, Denmark-Norway was forced to seek peace, and the Treaty of Kiel ended the war on 15 January 1814. Denmark-Norway had to cede Heligoland to Britain and all of Norway to the King of Sweden, while Denmark did get back the island of Anholt.