The Territory of the Saar Basin (German: Saarbeckengebiet, Saarterritorium; French: Territoire du bassin de la Sarre) was a region of Germany occupied and governed by the United Kingdom and France from 1920 to 1935 under a League of Nations mandate. It had its own flag (adopted on July 28, 1920): a blue, white, and black horizontal tricolour. The blue and white stood for Bavaria, and white and black for Prussia, out of whose lands the Saar Territory was formed. Initially, the occupation was under the auspices of the Treaty of Versailles. Its population in 1933 was 812,000, and its capital was Saarbrcken. 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 returned to Germany.

A referendum (plural: referendums or less commonly referenda) is a direct vote by the electorate on a proposal, law, or political issue. This is in contrast to an issue being voted on by a representative. This may result in the adoption of a new policy or specific law, or the referendum may be only advisory. In some countries, it is synonymous with or commonly known by other names including plebiscite, votation, popular consultation, ballot question, ballot measure, or proposition.

Some definitions of 'plebiscite' suggest it is a type of vote to change the constitution or government of a country. The word, 'referendum' is often a catchall, used for both legislative referrals and initiatives.