Zoroastrianism the national religion of ancient Iran. Zoroastrianism suffered a steep decline after the seventh century A.D. because of conversion to Islam. Of a remnant of roughly 100,000 adherents today, three-fourths are Parsis (‘Persians)’ in or from western India; the others are Iranian Zoroastrians. The tradition is identified with its prophet; his name in Persian, Zarathushtra, is preserved in German, but the ancient Greek rendering of that name, Zoroaster, is the form used in most other modern European languages. Zoroaster’s hymns to Ahura Mazda (‘the Wise Lord’), called the Gathas, are interspersed among ritual hymns to other divine powers in the collection known as the Avesta. In them, Zoroaster seeks reassurance that good will ultimately triumph over evil and that Ahura Mazda will be a protector to him in his prophetic mission. The Gathas expect that humans, by aligning themselves with the force of righteousness and against evil, will receive bliss and benefit in the next existence. The dating of the texts and of the prophet himself is an elusive matter for scholars, but it is clear that Zoroaster lived somewhere in Iran sometime prior to the emergence of the Achaemenid empire in the sixth century B.C. His own faith in Ahura Mazda, reflected in the Gathas, came to be integrated with other strains of old Indo-Iranian religion. We see these in the Avesta’s hymns and the religion’s ritual practices. They venerate an array of Iranian divine powers that resemble in function the deities found in the Vedas of India. A common Indo-Iranian heritage is indicated conclusively by similarities of language and of content between the Avesta and the Vedas. Classical Zoroastrian orthodoxy does not replace the Indo-Iranian divinities with Ahura Mazda, but instead incorporates them into its thinking more or less as Ahura Mazda’s agents. The Achaemenid kings from the sixth through the fourth centuries B.C. mention Ahura Mazda in their inscriptions, but not Zoroaster. The Parthians, from the third century B.C. to the third century A.D., highlighted Mithra among the Indo-Iranian pantheon. But it was under the