Reichsgau Wartheland
The Reichsgau Wartheland (initially "Reichsgau Posen", also: Warthegau) was a Nazi German "Reichsgau" formed from parts of Polish territory annexed in 1939 during World War II. It comprised the region of Greater Poland and adjacent areas. Parts of "Warthegau" matched the similarly named pre-Versailles Prussian province of Posen. The name was initially derived from the capital city, Posen (Poznań), and later from the main river, Warthe (Warta).