In 1807 Napoleon created a powerful outpost of his empire in Eastern Europe.
Poland had recently been partitioned by its three large neighbors, but Napoleon created the Grand Duchy of Warsaw, which depended on France from the very beginning. The Duchy consisted of lands seized in Russia, Austria, and Prussia; its Grand Duke was Napoleon’s ally the king of Saxony, but Napoleon appointed the intendants who ran the country.
The population of 4,3 million was released from occupation and by 1814 sent about 200,000 men to Napoleon’s armies. That included about 90,000 who marched with him to Moscow; few marched back. The Russians strongly opposed any move toward an independent Poland and one reason Napoleon invaded Russia in 1812 was to punish them.
The Grand Duchy was dissolved in 1815 and Poland would not be a state until 1918. However Napoleon’s impact on Poland was dramatic, including the Napoleonic legal code, the abolition of serfdom, and the introduction of modern middle class bureaucracies.