What led to the end of Napoleon reign end?

Answer 1

Napoleon III's foreign policy led to the end of his reign, as opposed to his domestic projects like his economic expansion, industrialization, public works, and support of the arts.

Specifically, Napoleon III's choice to give in to German taunts and get involved in the Franco-Prussian War of 1870-1871 was what ended his reign. Early in the war, he and his army were captured in the Battle of Sedan. Napoleon III became a prisoner of war and the Third French Republic was declared in his absence.

Frances defeat in the Franco Prussian War of 1870.

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War with Prussia was what ended his reign.