Finnish War begins: Russian invasion of Finland
- When
- 1807–1808
- Where
- Saint Petersburg; Ahvenkoski; Helsinki
- Episodes
- 3
The Finnish War began in February 1808 when Russian forces crossed into Finland following a diplomatic ultimatum regarding the Continental System. Russian troops occupied Helsinki and threatened the Sveaborg fortress, later taking Tampere. These initial moves, driven by Alexander I's alliance with Napoleon, set the stage for the eventual cession of Finland to Russia.
Episodes
- Russian Ultimatum to Sweden
Russia demanded Sweden join the Continental System, warning of action if Sweden did not comply.
- Crossing into Finland
Russian troops crossed the border into Finland without a declaration of war.
- Occupation of Helsinki
Russian forces occupied Helsinki and began bombarding the Sveaborg fortress.
Background and detail
Background. Following the Treaty of Tilsit, Alexander I demanded Sweden join the Continental System. When Sweden refused, citing British control of Baltic ports, Russia warned of action. Despite warnings, Swedish King Gustav IV Adolf ignored the threat, believing winter defense was impossible. This diplomatic failure led to the outbreak of war in February 1808.
Initial Invasion. On February 21, 1808, Russian troops under General Buxhoeveden crossed the border at Ahvenkoski, taking Loviisa. The invasion occurred without a formal declaration of war. Russian forces quickly advanced, occupying Helsinki in early March and beginning to bombard the Sveaborg fortress, which had been prepared for a long siege.
People involved
- Alexander I of Russia · Emperor of Russia
- Gustav IV Adolf of Sweden · King of Sweden
- Friedrich Wilhelm von Buxhoeveden · Commander of Russian army in Finland
Sources
- Finnish War Wikipedia, revision of 2026-08-22
- Suomenlinna Wikipedia, revision of 2026-10-01
- Alexander I of Russia Wikipedia, revision of 2026-09-27
Machine-drafted from the cited Wikipedia passages and checked by a reviewing model, not by a human editor. Every passage cites the revision it was written from; dates and places follow those passages.