What was the date of the prussian advance on paris

beginning of the Franco-Prussian War in July 1870

Explanation:

September 1

Explanation:

With the beginning of the Franco-Prussian War in July 1870, French forces suffered a string of serious reverses at the hands of the Prussians. Following their decisive victory at the Battle of Sedan on September 1, the Prussians quickly advanced on Paris and encircled the city.

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