The Province of Oulu was established in 1775 when Finland was an integrated part of Sweden from the northern part of
Ostrobothnia County. The new province was named after its administrative seat of
Oulu. As a consequence of the tumultuous conflicts of the
Napoleonic Wars,
Sweden had allied itself with the Russian Empire,
United Kingdom and the other parties of the
Fourth Coalition against
Napoleonic France. However, following the treaty of
Treaty of Tilsit in 1807, Russia made peace with France and left the coalition. This enabled Russia in 1808 to challenge Sweden in the
Finnish War, over the control of Finland. In the
Treaty of Fredrikshamn on 17 September 1809 Sweden was obliged to cede all its territory in Finland, to Russia. The ceded territories became a part of the Russian Empire and were reconstituted into the Grand Duchy of Finland, with the Russian Tsar as Grand Duke. The Province of Oulu was expanded in 1809 with the parts of the
Västerbotten County (eastern part of the
Torne Valley and historical
Lapland). After Finland became independent from Russia, in 1917, there were no changes in Oulu Province until 1938, when the northern part was split off and established as the
Lapland Province. All the provinces of Finland were abolished on 1 January 2010. == Administration ==