Episode 1 of 2

Cession of Finland

When: 1809
Where: Finland
Part of: Peace of Hamina (Treaty of Fredrikshamn) ends the Finnish War, 17 September 1809

Finland was ceded to Russia, becoming an autonomous Grand Duchy within the Russian Empire, a significant loss for Sweden.

As a result of the war, the eastern third of Sweden was established as the autonomous Grand Duchy of Finland. The cession represented a bitter loss for the Kingdom of Sweden. The treaty established Finland as a true autonomous grand duchy within the Russian Empire.

Sources

Finnish War Wikipedia, revision of 2026-08-22
Grand Duchy of Finland Wikipedia, revision of 2026-09-16

Machine-drafted from the cited Wikipedia passages and checked by a reviewing model, not by a human editor. Every passage cites the revision it was written from; dates and places follow those passages.