The Bolshevik seizure of power in Petrograd ended Russia's Provisional Government and triggered a civil war that resulted in the founding of the Soviet Union.
Key Facts
- Date (New Style)
- 7 November 1917
- Date (Old Style)
- 25 October 1917
- Key site captured
- Winter Palace, Petrograd
- Initial assault casualties
- None reported
- Resulting civil war duration
- Until late 1922
- Outcome
- Formation of the Soviet Union in 1922
By the Numbers
Location
Cause → Event → Consequence
The February Revolution of 1917 had toppled Tsar Nicholas II and installed a Provisional Government under Alexander Kerensky. That government remained deeply unpopular for continuing Russia's involvement in World War I, violently suppressing protest during the July Days, and failing to address workers' grievances, prompting urban soviets and the Bolshevik Party to organize a military uprising.
On 7 November 1917 (New Style), Bolshevik Red Guards under the Military-Revolutionary Committee—backed by sailors and tens of thousands of soldiers—seized key government buildings across Petrograd. In the early hours of 8 November, they captured the Winter Palace, overthrowing the Provisional Government and transferring power to the soviets under Bolshevik leadership directed by Vladimir Lenin and Leon Trotsky.
The revolution was not universally recognized, plunging Russia into a civil war that lasted until late 1922 and ultimately produced the Soviet Union. It inspired communist movements worldwide, prompted Western Allied military intervention against the Bolsheviks, and became the foundational event of Soviet state ideology, commemorated annually as October Revolution Day throughout the USSR's existence.