The Reichsgau Wartheland 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).
Poles being led to trains under German Army escort, as part of the ethnic cleansing of the areas of western Poland annexed to the Reich immediately following the invasion of 1939
A Reichsgau was an administrative subdivision created in a number of areas annexed by Nazi Germany between 1938 and 1945.
Propaganda postcard of Nazi Germany depicting the Gaue of the Reich (October 1939)