Administrative divisions of Weimar Germany

Upon the conclusion of World War I, Germany suffered significant territorial losses from the Treaty of Versailles. After the German Revolution, the 21 constituent states of Germany abolished their monarchies and continued as republics alongside the three pre-existing city-states within the new Weimar Republic. The former Ernestine duchies continued briefly as republics before merging to form the state of Thuringia in 1920, except for Saxe-Coburg, which became part of Bavaria. Additionally, the Saar Basin and the city of Danzig were detached from Germany and placed in the care of the League of Nations.

These states were effectively abolished under the Nazi regime by a series of Reichsstatthalter decrees between 1933 and 1935, which caused them to be superseded by Nazi provinces called Gaue. Many of the states were formally dissolved by the Allies at the end of World War II and ultimately re-organised into the modern states of Germany.

After World War I, the Saar Basin was occupied and governed jointly by the United Kingdom and France from 1920 to 1935 under a League of Nations mandate. After a plebiscite was held in 1935, the region was returned to Germany.

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