[2] The region served as the center of the empire until its conquest by the Macedonian king Alexander the Great (r. 336–323 BC).

[2] Since the end of the 3rd or the beginning of the 2nd century BCE, Persis was ruled by local dynasts subject to the Hellenistic Seleucid Empire.

[1] These dynasts held the ancient Persian title of frataraka ("leader, governor, forerunner"), which is also attested in the Achaemenid-era.

[1] The frataraka were shortly afterwards replaced by the Kings of Persis, most likely at the accession of the Arsacid monarch Phraates II (r. 132–127 BC).

171–138 BC), but visibly allowed local rulers to remain, and permitted the emission of coinage bearing the title of Mlk ("King").

[8] The Iranologist Touraj Daryaee argues that the reign of Vologases V was "the turning point in Parthian history, in that the dynasty lost much of its prestige.

However, Daryaee considers this statement unlikely, and states that it was in reality Shapur that helped Pabag to capture Istakhr, as demonstrated by the latter's coinage which has portraits of both them.

[8][11] Ardashir in an act of defiance, left for Ardashir-Khwarrah, where he fortified himself, preparing to attack his brother Shapur after Pabag's death.