Administrative divisions of the Sasanian Empire
The administrative divisions of the Sasanian Empire were administrative divisions of the state organisation of the Sasanian Empire. Administration. On his coinage, the first Sasanian King of Kings ("shahanshah") Ardashir I (), introduces himself as King of Kings of a realm that he identified as "Eran". His son and successor Shapur I () calls himself King of Kings of "Eran" and "Aneran" in his SKZ inscription. According to the inscription, "Eran" was made up of the following provinces ("shahr" in Middle Persian): A similar list is mentioned in the Ka'ba-ye Zartosht of the 3rd-century  Zoroastrian priest Kartir. The provinces of the late Sasanian realm are listed in the "Bundahishn" and "Vendidad". Provinces were split into smaller administrative divisions, particularly the "khwarrah" (same origin as the Iranian/Zoroastrian concept "khwarrah", "glory/fortune"), "rostag" or "tasug" (districts), and "dehs" (villages). These divisions were not always used all over the realm, and records of other units are known, such as an "awestam", which was ostensibly akin to a "shahr" and was administered by an "awestamdar". During the reforms of Kavad I () and his son and successor Khosrow I (), the provinces were grouped into four frontier regions ("kusts ), with a marshal (spahbed") in charge of each district; a chancery was also added to keep the soldiers equipped. Before Kavad and Khosrow's reforms, the Iranians' general ("Eran-spahbed") managed the empire's army. A new priestly office was also created known as the "advocate and judge of the poor" ("driyōšān jādag-gōw ud dādwar"), which assisted the clergy to help the poor and underprivileged (an obligation they had possibly ignored previously). Hierarchical list of Sasanian administrators and their level of authority. According to modern historian Negin Miri, the list of Sasanian administrators and their level of authority presented  in a hierarchical model was the following: