After the Russian Emperor Alexander I concluded the 1807 Treaty of Tilsit with Napoleon, he demanded that the Swedish King Gustav IV Adolf should join the alliance with France and Russia against the Great Britain. But Sweden and Great Britain had good commercial relationships. This led to open conflict between Sweden and Russia. The war began when the Russians, without declaring war, crossed the border on February 21, 1808. The war's largest battles were fought in Ostrobothnia and North Savo. In order to get information from the local people the Russians used violent and inhumane interrogation methods as well as bribery. The goal of the terrorist war against the civilian population was to break the people's resistance. Nevertheless, peasants rose up to protect their home community from the enemy's attacks.  

Historical war sources say little about how the events of the Finnish War affected local residents. But we know that the civilian population, against its will, was swept in many ways into the war and the hardship it brought. A lot of civilians died here during the Finnish War. The Russia won the war and Swedish-Finnish army surrendered in March 1809 and a permanent peace accord was signed in Hamina on September 17, 1809. Swedish rule ended with the Finnish war. Finland was regionally annexed to Russia, but its government was built on the basis of autonomy. The change of government changed Finland's status from a Swedish frontier province to a Grand Duchy of Russia. Soon after the peace agreement the Russian emperor Alexander the First granted Finland a state of autonomous grand duchy with its own laws and legal system and a basic freedom of religion. These changes were meant to strengthen the relationship with the Russian rulers and Finnish population.

A very important aspect of Russias annexation of Finland was the way in which it was carried out and the form that Finnish society assumed as a result. A Clear indication of Russias desire to make an independently functioning entity of Finland was the creation of the areas own capital. Under Swedish rule, Turku had been the centre of the province, but Finlands capital had of course been Stockholm. Now, with the decision to make Helsinki the new administrative centre, a new capital was created. The 19 th century was very important time period in Finlands history. It brought a growth of national pride. Old traditions and folklore was documented. New styles of art emphasized traditional tales and created a Finnish style of design. Finnish gained a state of official language along the Swedish and Russian. Finally Finland declared independence on 6th (sixth) of December 1917 and period of Russian grand duchy was over.