Treaty of Fredrikshavn 17 September 1809
The Treaty of Fredrikshavn resulted in Sweden relinquinishing ownership of Finland to Russia. Finland benefited greatly by this - rather than being merged into Russia it gained the status of an independent Grand Duchy.
How to cite this article: Dugdale-Pointon, TDP. (14 June 2004), Treaty of Fredrikshavn 17 September 1809, http://www.historyofwar.org/articles/treaty_fredrikshavn.html