Zoroastrianism is the ancient religion of Persia. It was founded about 2500 years ago (about the time of Cyrus) by the prophet Zarathushtra, also known as Zoroaster. It arose out of the polytheistic traditions of ancient India and Iran. Zarathushtra preached that there was one main God, whom he called Ahura Mazda. Ahura means "Lord," and Mazda means "Wise," so Zoroastrians call God the "Wise Lord." Zarathushtra has been known in the West as Zoroaster, from the Greek transliteration of his name; in Persia and India he is known as Zarthosht.