The Battle of Lyngør was a naval battle fought between Denmark-Norway and Britain in 1812 on the southern coast of Norway, effectively concluding the Gunboat War in Britain's favour and putting Denmark-Norway out of the war.

Denmark-Norway's attempt to remain neutral in the struggle between France and England and their respective allies early in the 19th century came to an end after England's preemptive naval actions of 1807, in which the entire Danish fleet was taken. The British imposed a blockade on supply lines between Norway and Denmark in the Skagerrak sound, except for Norwegian ships transporting lumber to Britain. The resulting blockade isolated Norway from both Denmark and from the market and was a catastrophe for Norway. Most exports were stopped, as well as grain imports from Denmark. The consequences were economic crisis, with hunger and severe famine due to the blockade.

The Norwegians preferred to limit military operations to coastal defence. Nevertheless, what was left of the Dano-Norwegian fleet after the Battle of Copenhagen (1807) fleet was committed to breaking the blockade. After years of skirmishes, the Dano-Norwegian fleet was reduced to one major ship, the frigate Najaden, which they had finished in 1811 with materiel salvaged from a ship-of-the-line destroyed in earlier battles. Najaden was under the command of Danish naval officer Hans Peter Holm.[1] Three brigs -- Kiel (under the command of Otto Frederick Rasch),[2] Lolland, and Samsøe -- accompanied Najaden.

The British saw an opportunity to enforce the blockade and break the back of Dano-Norwegian seapower. They therefore sent the 64-gun Third Rate ship-of-the-line Dictator and three brigs, the 18-gun Cruizer class brig-sloop Calypso, 14-gun brig-sloop Podargus and the 14-gun gun brig Flamer to seek out the Danes.

If you are interested in reading more about the battle plans and the actual battle, follow this link: http://en.wikipedia.org/wiki/Battle_of_Lyngør

The Battle of Lyngør effectively ended Denmark's involvement in the Napoleonic Wars. In the Treaty of Kiel, Denmark ceded dominion over Norway, setting the stage for Norway's independence movement, which finally achieved its aims in 1905. The battle also freed up British naval resources to fight France's navy in the Napoleonic Wars.
(excerpts are from the Wikipedia link above)

http://www.hjv.dk/MHV/Nyheder/Sider/DanmarkshistorieiNorge.aspx