Disputed German territories that fell under the League of Nations administration after the end of World War I were: Allenstein, Danzing, Marienweder, Memel, Saar, Schleswig and Upper Silesia. After World War I, the League of Nations used the plebiscite as a tool to resolve international borders in Europe that were undecided. ( Plebiscite is a Latin word meaning “referendum”.)  A vote for the citizens was held,  asking them to decide whether they wanted to become part of one nation or another. To publicise these referendums, stamps were often used as either overprinted or new stamps issued.