Like many other religions, Zoroastrianism frequently restructured its priestly organization during its long history, largely because of the environmental changes to which it was exposed. A major shift in status – from being the state religion in the Sasanian Empire to holding only a minor position in the early Islamic period – challenged the Zoroastrian hierarchy of authority. The Abbasid state provided Zoroastrianism with an opportunity to initiate a new office, which was called hu-dēnān pēšōbāy “Leader of the Zoroastrians”. This article is the first to deal with this office in detail and scrutinizes the concept of leadership (pēšōbāyīh) in Sasanian and Abbasid Zoroastrianism. It sheds some light on the priestly structure of Zoroastrianism in this period and investigates the position of the office within the overall religious organization. It re-examines, moreover, evidence for the officiating Zoroastrian theologians in this office at the Abbasid court in Baghdad. Finally, it searches for the parallels between this office and that of the East-Syrian catholicos and the Jewish exilarch.
