The dominant religion of Persia for more than a millennium preceding the Mohammedan invasion (636), founded on the teachings of the prophet Zarathustra. (Zoroaster is the corrupt Greek form of the Iranian Zarathustra.) The historical personality is practically lost in the legendary promulgations of the followers. Although disputed, the most logical date of his birth is about the sixth or fifth century b.c. in Iran. At the age of thirty or a little later, Zarathustra had a life-changing religious experience in which he met Ahura-Mazda (“the Wise Lord”). This experience plus other revelations led him to become the prophet of a new, purified religion. Tradition says this new prophet was successful in converting King Vishtaspa, the ruler of E Iran, and found a powerful protector of the faith in Vishtaspa's son, Darius the Great. Zarathustra died at age seventy-seven.