Written by A standalone piece
Josephus had no stake in the antiquity or prestige of the Magi. He was a first-century Jewish historian, recounting the Persian succession on the way to the story he cared about — the return from exile and the rebuilding of the Temple. That is exactly what gives one of his lines its weight. In passing, with nothing to prove, he records the Magi as an institution powerful enough to seize the throne of the Persian empire. A witness who sets down a fact against no agenda of his own is among the most credible kinds there is, and on the Magi, Josephus is precisely that.
The passage
Recounting how Darius came to the Persian throne, Josephus writes that after the slaughter of the Magi, who, upon the death of Cambyses, attained the government of the Persians for a year, the seven leading families of the Persians appointed Darius, the son of Hystaspes, to be their king.[^1]
The date, and what it fixes
The death of Cambyses falls in 522 BCE. So Josephus places the Magi at the center of imperial power in that year — and not as some marginal sect, but as a body able to seize and hold the government of the largest empire the world had yet seen, for a full year, until the Persian nobility restored the crown to Darius.
An institution does not reach that kind of power from nothing. To take the throne of the Achaemenid empire, the Magi had to be entrenched, organized, and long-established — a priesthood rooted deep in the Persian and Median world, not a recent arrival. Josephus’s sentence, written with no such point in mind, documents the Magi as a major power at the Persian court in the generation immediately after Cyrus the Great.
And he does not stand alone. Herodotus, writing earlier and closer to the events, tells the same story of the Magian seizure and its undoing, and names the Magi as the priestly class of the Persians.[^2] Two independent witnesses — one Greek, one Jewish, neither with any motive to inflate the point — place the Magi at the heart of the Persian court in the late sixth century BCE.
The Zoroastrian priesthood at the heart of the empire
The Magi were, in all probability, the priesthood of the Persian religion centered on Ahura Mazda — the clergy named in the royal inscriptions of Darius, and the body that became and remained the Zoroastrian priesthood.[^3] So what these sources record is the standing of the Zoroastrian priesthood at the Persian court by the time of Cyrus: not a late or peripheral presence, but an establishment powerful enough to reach for the empire itself.
This is what favors the broader picture. The religion of Ahura Mazda was not some newcomer in the Achaemenid world; its clergy were entrenched at the center of Persian power in 522 BCE, the generation after Cyrus, and were formidable enough to take the throne. The prophet’s own antiquity reaches back far earlier still — into the second millennium, on the evidence of the archaic language of his Gathas — but that is the clock of the founder; this is the clock of his priesthood, and it shows the Magi already a great power at the heart of the empire in the sixth century.[^4]
The witness who wasn’t trying
The strength of all this is that Josephus was not arguing for any of it. He recorded the Magi’s grip on the Persian throne because it was simply part of the history that brought Darius to power and the Jews home to Jerusalem. And in doing so, an outside hand — a Jewish historian, writing centuries later, with no brief for Persia’s faith — set down the Zoroastrian priesthood as a great power at the center of the Persian world in the generation after Cyrus. Entrenched at the heart of the empire, and attested by those who had no reason to flatter them.
Notes
[^1]: Flavius Josephus, Antiquities of the Jews 11.3.1 (Whiston translation), on the Magi seizing the government of the Persians after Cambyses’s death and the accession of Darius.
[^2]: Herodotus, Histories 3.61–79, on the Magian usurpation and its overthrow, and 1.101, identifying the Magi as a tribe of the Medes and the Persian priestly class.
[^3]: On the Magi as, in all probability, the priesthood of the Persian Ahura-Mazda religion and the body that became the Zoroastrian clergy, see Mary Boyce, Zoroastrians: Their Religious Beliefs and Practices (London: Routledge, 1979), and Albert de Jong, Traditions of the Magi: Zoroastrianism in Greek and Latin Literature (Leiden: Brill, 1997); and the invocation of Ahura Mazda in the Achaemenid royal inscriptions from Darius I (e.g., the Behistun Inscription).
[^4]: On the second-millennium antiquity of Zarathustra himself, indicated by the archaic Old Avestan of the Gathas, see Mary Boyce, A History of Zoroastrianism, vol. 1 (Leiden: Brill, 1975), and Helmut Humbach et al., The Gāthās of Zarathushtra (Heidelberg: Winter, 1991).