This is a chronology of battles and events of the Finnish War (1808-1809). The dates are according to the Gregorian (Western European) calendar. Russian sources might refer to Julian calendar dates.
| Date | Event | Location | Coordinates |
|---|---|---|---|
| February 21, 1808 (c. 5:00 a.m) | Russian army crosses the border to Finland | Kymi river, border river, near Hamina. | ? |
| March/April, 1808 | Russian army | Kuopio, Tampere, Jakobstad | ? |
| March/April, 1808 | Russian navy | Gotland, Åland Islands | ? |
| March 18, 1808 | The Russian army conquers the Fortress of Svartholm | Loviisa | ? |
| March 21, 1808 | The Russian army conquers the Hanko Peninsula | ? | |
| March 22, 1808 | The Russian army conquers Turku | ? | |
| April 6, 1808 | Cronstedt, who is the commander of the Fortress of Suomenlinna, negotiates with the Russian army | ? | |
| April 16, 1808 | Battle of Pyhäjoki | Pyhäjoki | ? |
| April 18, 1808 | Battle of Siikajoki | ? | |
| April 27, 1808 | Battle of Revolax | ? | |
| May 2, 1808 | Battle of Pulkkila | ? | |
| May 3, 1808 | Siege of Sveaborg | Suomenlinna at Helsinki | ? |
| May 9, 1808 | Battle of Kumlinge | ? | |
| June 19-20 , 1808 | Battle of Lemo | ? | |
| June, 1808 | Alexander I calls for elections and invites Finnish representatives to gather in Saint Petersburg. The deputies are led by Carl Erik Mannerheim. | ? | |
| June 24, 1808 | Battle of Nykarleby | Nykarleby | ? |
| June 25, 1808 | Battle of Vaasa | Vaasa | ? |
| June 30, 1808 | Battle of Rimito Kramp | ? | |
| July 11, 1808 | Battle of Kokonsaari | ? | |
| July 14, 1808 | Battle of Lapua | ? | |
| August 2-3 , 1808 | Battle of Sandöström | ? | |
| August 10, 1808 | Battle of Kauhajoki | ? | |
| August 17, 1808 | Battle of Alavus | ? | |
| August 21, 1808 | Battle of Karstula | Karstula | ? |
| August 28, 1808 | Battle of Lappfjärd | ? | |
| August 30, 1808 | Battle of Grönvikssund | ? | |
| September 1, 1808 | Battle of Ruona | ? | |
| Battle of Ruona and Salmi | ? | ||
| September 2, 1808 | Battle of Salmi (same as above?) | ? | |
| September 6, 1808 | Battle of Ömossa | Ömossa | ? |
| September 13, 1808 | Battle of Jutas | Nykarleby | ? |
| September 14, 1808 | Battle of Oravais | Oravais | ? |
| September 18, 1808 | Battle of Palva Sund | ? | |
| September 29, 1808 | Truce of Lohteå | ? | |
| October 27, 1808 | Battle of Koljonvirta | ? | |
| November 10, 1808 | The Moonlight Raid | ? | |
| November 19, 1808 | Convention of Olkijoki: the Finnish army retreats north of the Kemi River | ? | |
| March 21, 1809 | Convention of Åland | ? | |
| March 25, 1809 | Convention of Seivis/Kalix, after Russian navy raids in Gulf of Bothnia | ? | |
| March 25-July 19, 1809 | Diet of Porvoo | ? | |
| May 15, 1809 | Encounter at Skellefteå | ? | |
| July 5-6 , 1809 | Battle of Hörnefors | ? | |
| August 19, 1809 | Battle of Sävar | ? | |
| August 20, 1809 | Battle of Ratan | ? | |
| August 25, 1809 | Battle of Piteå | Piteå | ? |
| September 2, 1809 | Truce of Frostkåge gästgivargård | ? | |
| September 17, 1809 | Treaty of Fredrikshamn | ? |