Zoroastrianism /ˌzɒroʊˈæstriənɪzəm/, also called Zarathustraism, Mazdaism and Magianism, is an ancient Iranian religion and a religious philosophy. It was once the state religion of the Achaemenid, Parthian, and Sasanian empires.[1] Estimates of the current number of Zoroastrians worldwide vary between 145,000 and 2.6 million.[2]

Zoroastrianism arose in the eastern region of the ancient Persian Empire, when the religious philosopher Zoroaster simplified the pantheon of early Iranian gods[3] into two opposing forces: Spenta Mainyu (Progressive mentality) and Angra Mainyu (Destructive Mentality) under the one God, Ahura Mazda (Illuminating Wisdom).[4][5]

Zoroaster's ideas led to a formal religion bearing his name by about the 6th century BCE and have influenced other later religions including Judaism, Gnosticism, Christianity and Islam.[6]..

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