In this work to the study of Thraco-Persian relations at the turn of the VI-–V centuries BC involved originating from Persepolis household archives of time of Darius I. The article analyzes the Persian ethnic name Skudra and the possibility of its application to peoples European Thrace, part of which was conquered by Darius during the Scythian campaign. Then provides specific information about the Thracian workers contained in the Persepolis fortification archive, and analyzes the legal status of them in the Royal household.