Why did Napoleon invade Russia in 1812?

Napoleon’s invasion of Russia in 1812 was primarily driven by the collapse of the Continental System, an economic blockade designed to isolate and weaken Great Britain.12

By 1810, the blockade had caused significant economic hardship in Russia, leading Tsar Alexander I to issue a decree on December 31, 1810, that opened Russian ports to neutral shipping and British goods. This act effectively ended the Franco-Russian alliance established by the Treaties of Tilsit in 1807.23

Beyond the economic conflict, tensions were fueled by:
* Geopolitical Rivalry: Napoleon sought to humble Russia, which he viewed as a "colossus of Northern barbarism," and exclude it from European influence.1
* The Duchy of Warsaw: The presence of this French-controlled state on Russia’s border was perceived by the Tsar as a direct threat.2
* Diplomatic Slights: Relations worsened after Napoleon’s marriage to the Austrian archduchess Marie-Louise, which followed the rejection of his proposal for a marriage alliance with the Russian imperial family.3

Ultimately, Napoleon invaded to enforce the blockade and reassert his hegemony over the continent, viewing the campaign as a necessary step to secure his empire.12