The district was created in 1816 when the area became the property of Prussia. After World War I the Saar area was under special government of the League of Nations, which did split the district into two parts. The area around Wadern stayed Prussian, while the Merzig area became part of the Saargebiet area. In 1935 the Saar area rejoined Germany, however it took till after the World War II that the two district parts were reunited in 1946.