Abstract
In this paper, similarities and differences between Parthian vassal kingdoms and Roman client states are analyzed. From the perspective of the imperial periphery, the room for manoeuvre of the client kings and the vassal rulers between the two great empires and their political strategies and goals are analysed: Despite their subordination to Rome or Parthia, the petty rulers between Syria and Iran also pursued independent political goals that could conflict with the interests of their imperial superiors. By friendly relations with the other empire they secured themselves more options for action and were able to react flexibly to a crisis when the power of their overlord was threatened. The petty ruler’s first aim was the strengthening of their political position both within the hierarchy of their own empire and in the local rivalry between the monarchs of the Middle East across the imperial borders.