The Territory of the Saar Basin, also referred as the Saar or Saargebiet, was a region of Germany occupied and governed by the United Kingdom and France from 1920 to 1935 under a League of Nations mandate. Initially, the occupation was under the auspices of the Treaty of Versailles. The Territory closely corresponds with the modern German state of Saarland, but was slightly smaller in area. After a plebiscite was held in 1935, it was restored to Germany. After WWII, France occupied Saar and late established a protectorate. The provisional semi-independent state of Saar was established Jan.1, 1951. France returned the Saar to the German Federal Republic Jan.1, 1957.