Why was the invasion of russia so disastrous for napoleon's army and for france

Invading Russia proved disastrous because of a few reasons:

1) Timing of invasion: While France invaded towards the middle of summer (the best time is summer), it just wasn't enough time to take over the strategic areas before winter set in, leading to the French defeat and eventual retreat from Russia.

2) Sheer size: Russia stretched across Eurasia, and because of this large extent covering thousands of square miles, Napoleon had a hard time locating and decisively taking over the land and guarding it, which led to infiltration, sabotage, and spies from the Russian empire.

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