From 1933 onward, after the Nazi seizure of power, the Gaue increasingly replaced the German states as administrative subdivisions in Germany.

[1] In 1940, after Germany occupied the French region of Alsace, Gau Baden incorporated the two Alsatian départements of Bas-Rhin and Haut-Rhin, becoming Baden-Elsass.

The seat of the Gau administration was originally Karlsruhe, but moved to Strasbourg after the German occupation of France.

[2] At the head of each Gau stood a Gauleiter, a position which became increasingly more powerful, especially after the outbreak of the Second World War, with little interference from above.

Local Gauleiters often held government positions as well as party ones and were in charge of, among other things, propaganda and surveillance and, from September 1944 onward, the Volkssturm and the defense of the Gau.