A Reichsgau was a province within the Greater Germany of 1938 to 1945 (from the start of territorial annexation to the fall of the Third Reich). It was formed from the words "Reich", meaning "realm" or "empire" and "gau", a deliberately medieval-sounding word meaning "shire" or "region". There were several Reichsgaue, namely the annexes of Austria, Sudetenland, Wartheland and Danzig-Westpreussen. These regions were each governed by a NSDAP (more generally known as the Nazi Party) official, known as a Gauleiter or "region leader". It is perhaps significant that only 5 of the Gauleiter ever graduated from either a university or a technical school. The rest of Germany, i.e. Germany pre-1938, de jure continued to be divided into Länder, although de facto the "Gaue" of the Nazi Party organization were more important as local units in these areas as well. Grossdeutschland (literally Greater Germany) is a term that has been used in two separate contexts over history. ... Nazi Germany, or the Third Reich, commonly refers to Germany in the years 1933–1945, when it was under the firm control of the totalitarian and fascist ideology of the Nazi Party, with the Führer Adolf Hitler as dictator. ... Reich is the German word for realm or empire, cognate with Scandinavian rike and Dutch rijk. ... Historically, Gau (plural Gaue) was an old Frankish term for the politico-geographical division of a nation. ... The Sudetenland was part of Germany until 1806. ... Reichsgau Wartheland (initially Reichsgau Posen) was the name given by Nazis to the territory of Greater Poland which was occupied, annexed and directly incorporated into the German Reich after defeating the Polish army in 1939 (as opposed to the General Government, GG). ... The Reichsgau Danzig-West Prussia (Danzig-Westpreussen) was a German administrative unit created in 1939 from Freie Stadt Danzig and Polish Pomerania. ... The Nazi swastika The National Socialist German Workers Party (German: Nationalsozialistische Deutsche Arbeiterpartei), better known as the NSDAP or the Nazi Party was a political party that was led to power in Germany by Adolf Hitler in 1933. ... The Nazi swastika symbol The National Socialist German Workers Party ( German: Nationalsozialistische Deutsche Arbeiterpartei), better known as the NSDAP or the Nazi Party was a political party that was led to power in Germany by Adolf Hitler in 1933. ... A Gauleiter was a leader of a local branch of the NSDAP (more commonly known as the Nazi Party) or the head of a Reichsgau (an administrative division of the state). ... A Gauleiter was a leader of a local branch of the NSDAP (more commonly known as the Nazi Party) or the head of a Reichsgau (an administrative division of the state). ... 1938 was a common year starting on Saturday (link will take you to calendar). ...
ReichsgauWartheland (initially Reichsgau Posen) was the name given by Nazis to the largest subdivision of the territory of Greater Poland which was directly incorporated into the German Reich after defeating the Polish army in 1939.
After the invasion of Poland, the conquered territory was partitioned among four different Reichsgau and the General Government area further east.
Militärbezirk Posen was created in September 1939 and as Reichsgau Posen annexed to Germany on October 8, 1939, with Arthur Greiser as the first and only Gauleiter.