Finnish War

Finnish War
Part of the Napoleonic Wars and a series of Russo-Swedish wars
Left to right from the top: Siege of Sveaborg Battle of Revolax Battle of Oravais Sven Dufva (epic poem) at the Battle of Koljonvirta Battles of Sävar and Ratan
Date 21 February 1808 – 17 September 1809 (1 year, 6 months, 3 weeks and 6 days) Location Finland and Sweden Result Russian victory Treaty of Fredrikshamn Territorial changes Sweden loses Finland, Åland, a part of Lapland and a part of West Bothnia, from which the Grand Duchy of Finland was constituted, an autonomous part of the Russian Empire.
Belligerents
Russian Empire Supported by: French Empire Denmark–Norway	Sweden Supported by: United Kingdom
Commanders and leaders
Alexander I Fyodor Buxhoeveden Bogdan von Knorring Alexey Arakcheev Barclay de Tolly Nikolay Kamensky Yakov Kulnev Pyotr Bagration Nikolay Raevsky	Gustav IV Adolf Charles XIII Wilhelm Klingspor Carl Adlercreutz Johan Sandels Georg von Döbeln Carl Olof Cronstedt (POW) Eberhard von Vegesack
Strength
August 1808: 55,000	August 1808: 36,000
Casualties and losses
10,000 killed or wounded[1]	7,000 killed or wounded[1] 53,000 died of disease and other hardships[2]

The Finnish War (Swedish: Finska kriget, Russian: Финляндская война, Finnish: Suomen sota) was fought between the Kingdom of Sweden and the Russian Empire from 21 February 1808 to 17 September 1809 as part of the Napoleonic Wars. As a result of the war, the eastern third of Sweden was established as the autonomous Grand Duchy of Finland within the Russian Empire. Other notable effects were the Swedish parliament's adoption of a new constitution and the establishment of the House of Bernadotte, the new Swedish royal house, in 1818.