Zoroaster prophecy that saw a return of Sassanid emperor Bahram: Shoghi Effendi also stated that Zoroaster lived roughly 1000 years before Jesus. The Greeks—in the Hellenistic sense of the term—had an understanding of Zoroaster as expressed by Plutarch, Diogenes Laertius, and Agathias that saw him, at the core, to be the "prophet and founder of the religion of the Iranian peoples," Beck notes that "the rest was mostly fantasy". Zoroaster was set in the ancient past, six to seven millennia before the Common Era, and was described as a king of Bactria or a Babylonian (or teacher of Babylonians), and with
Zoroaster that the chronological calculation for Zoroaster was developed by Persian magi in the 4th century BCE, and as the early Greeks learned about him from the Achaemenids, this indicates they did not regard him as a contemporary of Cyrus the Great, but as a remote figure. Some later pseudo-historical and Zoroastrian sources (the "Bundahishn", which references a date "258 years before Alexander") place Zoroaster in the 6th century BCE, which coincided with the accounts by Ammianus Marcellinus from 4th century CE. The traditional Zoroastrian date originates in the period immediately following Alexander the Great's conquest of the Achaemenid Empire in