Warsaw, Duchy of

Independent Polish state (1807–15), created by Napoleon. Established by the Treaties of Tilsit in 1807 after the Poles had helped Napoleon defeat Prussia, it consisted originally of the major portion of the central Polish provinces that Prussia had taken in the 1790s. For Napoleon's second war against Russia (1812), the Duchy of Warsaw supplied nearly 98,000 men, but Napoleon's defeat in Russia also sealed the fortunes of the duchy. In 1813 the Russians assumed control of it. Later the Congress of Vienna divided it into three parts: the Grand Duchy of Poznan; the free Republic of Kraków; and the Congress Kingdom of Poland, which was joined to Russia by making the Russian emperor its king.