Zoroaster, c.628 B.C.-c.551 B.C., religious teacher and prophet of ancient Persia, founder of Zoroastrianism. Zoroaster, the name by which he is ordinarily known, is derived from the Greek form of Zarathushtra (or Zarathustra) [camel handler?], his Persian name. Zoroaster is believed to have been born in NW Persia. His youthful studies were crowned at the age of 30 by the first of a series of revelations of a new religion. His attempts to proselytize at home failed, and he fled east to ancient Chorasmia (now largely Iranian Khorasan), where he converted King Vishtaspa (who may have been Hystaspes, the father of Darius). The religion then spread rapidly through Vishtaspa's domain. The circumstances of Zoroaster's death are not known.

or Zarathustra

(born circa 628, probably Rhages, Iran—died circa 551 BCE) Iranian religious reformer and prophet, founder of Zoroastrianism and Parsiism. He was a priest in his tribal religion, with which he eventually became disillusioned. Having received a vision, he began teaching that Ahura Mazdā was the highest god and alone was worthy of worship, a concept that went against the polytheism of Iranian religion. He forbade the orgiastic rites that accompanied animal sacrifice, common in his time, but preserved the ancient cult of fire worship. After converting a king called Vishtāspa to his teachings, Zoroaster remained at the royal court. He became the subject of legends and a model for various occupations.

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