Separation of powers and authorities in ancient Iran (Sassanid and Parthian era)

Nowadays separation of powers is defined as distribution of ruling authorities among general social powers in order to prevent power centralization and emanation of despotism. Current separation of powers in Iran is not irrespective of its past history. However, separation of powers in ancient Iran carries special complexity and research on this issue as a general law topic about the government at that era seems problematic; but the present study granted the study of the ruling system tries to discover the separation of powers and delegation of authorities in a way that limited the governors authorities and public rights enforcement. With investigation of the Sassanid and Parthian ruling system, we intend to determine the factors supporting the assumption.