The article dwells upon the relations between the early Arsacids and the Greek and Iranian population of Parthyene and Hyrcania. It is noted that during the rule of Arsaces I and his immediate successors their power in this region was a kind of military occupation. It is concluded that it was only during Phraates I and Mithridates I reign that the conflict with the local population was settled, and the conditions for rapid growth of the power of the Parthian state were provided.
