The resulting enlarged Pomeranian voivodship was called Greater Pomeranian Voivodship ("Wielkopomorskie"). When Nazi Germany invaded Poland in September 1939, this Greater Pomeranian voivodship was first made the German military district "West Prussia", and by a decree of Adolf Hitler on 8 October merged with the Free City of Danzig and the East Prussian Regierungsbezirk West Prussia, to form the "Reichsgau" West Prussia. The western remains remained outside and continued to be administered by the German Pomeranian Gau as Regierungsbezirk Grenzmark Posen-West Prussia according to the 1938 reform, while the Bromberg (Bydogoszcz) region stayed with "Reichsgau" West Prussia and was not attached to "Reichsgau" Posen, the later "Warthegau". The designation "Reichsgau" instead of just "Gau" indicates that the province primarily consisted of annexed territory. A Gauleiter of a Reichsgau was also titled Reichsstatthalter. Other "Reichsgau"e were e.g. Reichsgau Wartheland and Reichsgau Sudetenland. Albert Forster, the Gauleiter of Danzig since 1930, was named Gauleiter and Reichsstatthalter on 26 October 1939. The Reichsgau was very heterogenous, like the territory, which comprised territory of the pre-war Danzig (completely), of Germany (West Prussia Government Region) and of Poland (roughly the Pomeranian Voivodeship), the population amounted to 2,179,000 altogether, with 1,494,000 Polish citizens of mostly Polish ethnicity, 408,000 Danzig citizens of mostly German ethnicity and 277,000 German citizens of mostly German ethnicity. The German occupiers considered the Danzig and Polish citizenships as naught, due to the de facto abolition of these two states. Christian Danzigers and Christian Poles of German ethnicity were granted German citizenship, Jewish Danzigers, and Jewish Poles of which ethnicity so ever were denied the German citizenship. As to Christian Danzigers and Christian Poles of Polish ethnicity the acceptance as citizens was mostly denied, but under certain circumstances granted. Nazi German policy aimed at extermination of Jewish and Polish population. Mass-murder sites in the region include:  Nazi policy to exterminate the Polish and Jewish populations was conducted in several phases; the first stage occurred in September 1939.