The 1806 Greater Poland Uprising was organized by General Jan Henryk Dąbrowski to help advancing French forces under Napoleon I in liberating Poland from Prussian occupation. The Wielkopolska Uprising was a decisive factor that allowed the formation of the Duchy of Warsaw (1806) and the inclusion of Wielkopolska in the Duchy of Warsaw. It was one of the three most successful (entirely victorious) uprisings in the history of Poland, in addition to the Greater Poland Uprising of 1918-1919 and Sejny Uprising.