Zoroaster lower right corner. The prophet is holding a star-studded globe. Zoroaster Zoroaster (, ; "Zōroastrēs"), (Persian: زرتشت pronounced as Zartusht) also known as Zarathustra (, ; "Zaraθuštra"), Zarathushtra Spitama, or Ashu Zarathushtra, was an ancient Persian prophet, spiritual leader and ethical philosopher who taught a spiritual philosophy of self-realization and realization of the Divine. His teachings challenged the existing traditions of the Indo-Iranian religion and later developed into the religion of Mazdayasna or Zoroastrianism. He inaugurated a movement that eventually became the dominant religion in Ancient Persia. He was a native speaker of Old Avestan and lived in the eastern
Zoroaster 330 BCE. The Seleucid rulers who gained power following Alexander's death instituted an "Age of Alexander" as the new calendrical epoch. This did not appeal to the Zoroastrian priesthood who then attempted to establish an "Age of Zoroaster". To do so, they needed to establish when Zoroaster had lived, which they accomplished by (erroneous, some even identified Cyrus with Vishtaspa) counting back the length of successive generations, until they concluded that Zoroaster must have lived "258 years before Alexander". This estimate then re-appeared in the 9th- to 12th-century Arabic and Pahlavi texts of Zoroastrian tradition, like the 10th century Al-Masudi