I want to know the answer to the following question:
Who was responsible for the creation of the Duchy of Warsaw?
All the background I'm provided with is that "Fryderyk Chopin was born in Żelazowa Wola, 46 kilometres (29 miles) west of Warsaw, in what was then the Duchy of Warsaw, a Polish state established by Napoleon.". Is that enough to answer the question?
Answer: yes