The district was created in 1834 when Prussia bought the Lichtenfeld area from Saxe-Coburg and Gotha. After World War I the Saar area came under special rulership of the League of Nations, and the Sankt Wendel district was split into two parts. The northern part, the Restkreis Sankt Wendel, was merged into the district Birkenfeld, the southern part stayed in the Saarland in its smaller size.
The district is located in the Saar-Hunsrück natural area, a hilly area with elevations between 200 and 600 meters. The main river in the district is the Nahe. The Bostalsee is the biggest tourist lake in the south-west of Germany, covering an area of about 1.2 km².
The blue lion represents the counts of Veldenz, a branch of the Wittelsbach family. The silver lion is taken from Nassau-Saarbrücken. The two counties had the most important possessions in the districts. The shield in the middle show a fleur-de-lis taken from the city Sankt Wendel, in the colours taken from the Lorraine.