Administrative division of the Duchy of Warsaw was based on departments, which were headed by prefects. It was a solution adopted after the French model, as the entire Duchy was in fact created by Napoleon, and based on French ideas, although the departaments were divided into traditional Polish powiats (counties). There were six initial departments, which had previously made Kingdom of Prussia’s province of South Prussia (1793/95 - 1807), but after the 1809 Polish–Austrian War, and the Treaty of Schönbrunn, their number increased to ten (as the Duchy territory was expanded following the annexation of West Galicia). Each department was named after its capital city.