Treaty of Hamina

The Treaty of Hamina, which was signed on 17 September 1809 and took effect on 13 October 1809, created a completely new framework for Finland’s position. While Sweden was compelled to cede larges territories, for Finland it meant the beginning of regional prosperity.

Västerbotten, east of the Rivers Tornionjoki and Muonionjoki, and nearly all of Tornio Valley Lappland were annexed to Finland to form a new province. An interesting issue in terms of international law was the plan to keep the Baltic Sea as a closed sea.