The municipality lies in the Hunsrück near Frankfurt-Hahn Airport, roughly 5 km west of Kastellaun.

Finds of coins and vessels bear witness to Celtic settlement on the Burgkopf, a nearby mountain spur, as do remnants of a Roman temple and two grave complexes that have been unearthed.

Beginning in 1316, Mastershausen, together with 15 neighbouring places, belonged to the Amt of Balduinseck in the Electorate of Trier.

The red cross is the arms formerly borne by the Electorate of Trier, to which Mastershausen belonged for more than 400 years.

The golden crown on the black field recalls Queen Richeza of Poland, who donated holdings at Malestreshusen to the Brauweiler Monastery.