General Confederation of the Kingdom of Poland
The General Confederation of the Kingdom of Poland (28 June 1812 – 30 April 1813; Polish Konfederacja Generalna Królestwa Polskiego) was a governing body of the Duchy of Warsaw created by Napoleon Bonaparte and the Polish political elite on the onset of Napoleon's campaign against Russia, which was proclaimed as "the second Polish war". It took the form of a confederated sejm (parliament).
Source: Wikipedia — General Confederation of the Kingdom of Poland (CC BY-SA 4.0)