This article presents an overview of the history of Zoroastrianism from its beginnings up to the 9th and 10th centuries CE. Details of different periods and specific issues relating to Zoroastrianism are discussed the relevant separate entries.

Owing to both the nature and availability of sources, it is difficult to write a comprehensive history of Zoroastrianism, as there are periods about which we know very little, others for which information is well restricted to circumscribed subjects or genres, and still others that must be reconstructed by reading back in time from the contents of later writings or by reading forward from the sources of cognate cultures. A survey of the important scholarly literature on the subject will reveal both areas of consensus and those of widely divergent opinion. While it is often possible to distinguish clearly fact from theory, one finds all too frequently that fact and theory are hard to disentangle one from the other.

Sources. The most important source for our knowledge of the ancient period of Zoroastrian history is the collection of scriptures known by its Middle Persian (Pahlavi) name Abestāg (Avesta). Written in an ancient Eastern Iranian language, Avestan, the Avesta is the great achievement of learned Zoroastrian priests who collected, edited, and codified a variety of written and oral traditions during the Sasanian period, that is, during an era far removed from the times when the constituent pieces of the tradition were composed. Those constituent pieces that have survived to today, however, represent only a fraction of what the Sasanian priests produced. During the reign of Ḵosrow I Anōširavān (531-79 CE), if not earlier, there existed a vast collection of texts consisting of twenty-one Nasks (parts). These Nasks had been composed partially in Avestan and partially in Pahlavi. In addition to much of the extant corpus of the Avesta, there were other Avestan texts that have since been lost, as well as a vast amount of texts written in Pahlavi, called zand “commentary,” which were either glosses of Avestan originals or compositions for which no Avestan ancestor had existed. Priest-scholars in the 9th and 10th centuries compiled extensive digests of these materials, such as the Dēnkard and the Bundahišn. In sorting through these digests, one must attempt to distinguish what may have had an ancient Avestan origin and what derives from Sasanian or even Arsacid sources. What this means to the historian is that the disposition of the scriptural sources is almost entirely non-contemporaneous with times and eras that one wants to understand through them. Furthermore, it is almost impossible to figure out the date with any degree of accuracy, since the constituent pieces of the Avesta deal to a great extent with matters of ritual, myth, and worship without any reliable ties to dateable events.

To gain a perspective on ancient western Iranian religious history one has the relatively small corpus of Achaemenid inscriptions contemporaneous with the events they report and, in addition, documents from the ancient Near East and the writings of Classical authors, of whom the most significant is Herodotus. Although Greek and Latin authors are important, sometimes sole sources for the span of time stretching from the Achaemenids through the Sasanians, they must always be approached with critical caution.

There is very little source material, indigenous or foreign, for the Seleucid and Arsacid periods. For the Sasanians there are the literary sources already discussed, inscriptions, especially important among them being that of the high priest Kirdēr, and a variety of writings on coins, silverware, etc.; in addition, we have Byzantine sources and historians of the Islamic period (e.g., Ṭabari, Ṱaʿālebi, Meskawayh) preserve much valuable information. For all periods, save the most ancient, art, architecture, and the material culture revealed by archeology provide information usually not present in the written record.

Ancient Iranian religion. Just as in the case of other religions that can be identified with a founder, whether Jesus, Māni, or Moḥammad, so too with Zoroastrianism, we find that the new religious movement was inspired and informed against an historical-cultural background peculiar to the founder. Thus, the history of Zoroastrianism cannot begin with Zarathustra, but rather with the reconstruction that we achieve of ancient Iranian religion. Matters are complicated by the fact that Zarathustra’s religious vision (daēnā, see DĒN) seems to have been slow in its spread among the Iranian peoples. Ancient forms of religion coexisted and intermingled with the new. An eventual synthesis occurred, quite different from the ruptures with the past that one finds in Christianity and Islam.

During the 3rd millennium, a large group of loosely associated tribes calling themselves Arya, living somewhere in central Asia and speaking related dialects of what is now known as the Indo-Iranian group of Indo-European languages, differentiated itself into two major linguistic and cultural groups. By the middle of the 2nd millennium one group was migrating into the Punjab region of the Indian subcontinent and into Anatolia, while the other group was migrating over the Iranian plateau. The Indo-Aryans who found themselves in the ancient Near East played a brief role in political and military affairs, but were soon absorbed by the dominant cultures. The Indo-Aryans who settled the Punjab and the Iranians (Mid. Pers. ērān, an old genitive plural *aryānām, Av. airyānąm “land of the Aryas”) soon overwhelmed the respective indigenous populations politically, linguistically, and culturally. Once sharing common religious ideologies and cultic practices, as they settled down, the two groups began to develop their religious lives along separate lines. Nevertheless, when the religious texts of both are studied together they provide a basis for reconstructing common features and for identifying innovations.

Central to both Iranians and Indo-Aryans was the sacrificial worship (Av. yasna-, OInd. yajñá-) of the gods (Av. daēva-, OPers. daiva, OInd. devá; see DAIVA, DĒV), in which an essential element was the preparation of the sacred drink (Av. haoma-, OPers. hauma-, OInd. sóma-; see HAOMA). They worshiped deities, some of whom bore the same or nearly identical names, for example, Miθra/Mitra, Vayu/Vāyu, Θwōrəštar/Tvaṣṭar, and some represented common concepts of divine functions, for example, Vərəθraγna/Indra (warrior), Spəntā Ārmaiti/Pṛthivī (Earth), Ātar/Agni (Fire). At the head of the Iranian pantheon stood Ahura Mazdā. He was a creator (dātar) in the sense that he exercised dominion over creation in establishing order and putting (vb. -) everything in its proper place. The actual crafting of the creation was the work of the demiurge, θwōrəštar- “craftsman.” Ahura Mazdā’s consort was the Earth, known by the name Spəntā Ārmaiti, though he seems to have had other wives, the Ahurānīs “wives of Ahura.” Ahura Mazdā had a particular connection to the cosmic principle of order and truth called aṧa- in Avestan (OInd. ṛtá-, OPers arta-), and like the supreme Vedic god Varuṇa, was a source of insight into Truth for poets, the divinely inspired creators of sacred hymns. Two male deities were closely associated with Ahura Mazdā. One was Rašnu “Judge,” who had a limited judicial function, analogous to that exercised by Varuṇa, in serving as the divine judge presiding over the oaths sworn by men. The other was Miθra. While Miθra was a complex deity, the essence of his being was that he was foremost the god “Covenant.” That is, he presided over all treaties between nations and covenants between people. The image of him as a mighty warrior riding in his chariot full of weapons reflects his ability to enforce the sanctity of covenants. As a warrior he shares much in common with another powerful deity Vərəθraγna (Mid. Pers. Wahrām, NPers. Bahrām) “Victory,” whose name etymologically means “the smashing of resistance” (AirWb., col. 1412; see BAHRĀM). As such he embodied the ideal of the Iranian warrior who was capable of smashing the defenses of all enemies (Boyce, 1975-82, I, pp. 62-65; Schwartz, pp. 671-73). Warriors invoked both Miθra and Vərəθraγna as they went into battle, yet, when it came to the exercise of legitimate temporal power and the success of the ruler in wielding that power, two other forces came into play. The Iranians developed a unique concept of an impersonal force called xᵛarənah- “glory,” conceived as a fiery presence that attached itself to legitimate rulers but remained unobtainable by illegitimate usurpers (see FARR[AH]; Bailey, pp. 1-51). Without this royal glory one could not hope to hold power. Whereas xᵛarənah- was an impersonal power, victory to the legitimate ruler and righteous warrior was granted by the goddess Anāhiti/Anāhitā (see ANĀHĪD), who maintained this role even into Islamic times, disguised as Šahrbānu. Like Athena and Ištar, she dispensed success in arms. (Schwartz, pp. 667-84).

The cosmos was basically three-tiered, consisting of earth, atmosphere, and heaven. The earth was divided into six concentric continents (karšvar) surrounding the central continent, Xᵛainiraθa (Mid. Pers. Xwanirah), where aryana vaējah (Mid. Pers. Ērān-Wēz) “the Iranian expanse” was located (Gnoli, 1980, pp. 88-90; idem, 1989, pp. 38-47; Benveniste, 1933-35; for various suggestions concerning its location, see Dandamaev, pp. 36-37). At the center of the earth was the cosmic mountain, Harā Bərəzaitī, the Alborz, which acted as the axis mundi. At its southern flank was the sacred Vouru-kaša sea (see FRĀXKARD), in the middle of which grew the Tree of Life (Av. Gaokərəna, Mid. Pers. Gōgirn). Over the earth and expanse of sky arched the stone vault of heaven (asman-) beyond which was the realm of the Infinite Lights (anaγra raočå), and the heavenly abode called the Best Existence (vahišta- ahu-), and the House of Song (garō.nmāna-,Mid. Pers. garōdmān). Below the earth was the realm of Infinite Darkness, (anaγra tə). The entire earth rested upon and was surrounded by the waters of chaos. Fresh water flowed down Harā in the river goddess Arədvī Sūrā, the Strong Moist, into the Vouru-kaša, and from it the various rivers of the world flowed, accumulating pollutants in their courses, to the salt sea called Pūitika, the Filterer, from which the hydrological cycle repeated itself (Boyce, 1975-82, I, pp. 135-36).

As far as one can reconstruct on the basis of Pahlavi sources, thought concerning the temporal dimension of the cosmos was in terms of a system of three or four world ages, analogous to the yuga system of ancient India and the four metallic ages of Greece, with each lasting three-thousand years. One can guess that there was an idea of the degradation of the cosmos over the course of the ages and that a complete cycle would have ended with a cataclysm and subsequent creation that renewed the cycle, though in its present form the cycle has been thoroughly transformed into a myth of creation, battle of good and evil, final triumph of the good and establishment of the eternal kingdom of God, Ohrmazd (see COSMOGONY AND COSMOLOGY i.). The yearly cycle was punctuated by various sacred festivals, which probably varied from region to region. The most important was the spring festival celebrating the new year (Phl. nōg rōz, New Pers. nowruz), preceded by a liminal time marking the return of the spirits of the dead, the frawašis (see FRAVAŠI; Gignoux, 2001, pp. 16-20).

The ancient Iranian cultic practices seem to have been very similar to those referred to in the Vedic literature. Men with special training were required and, as at later periods, the priestly functions may have been hereditary. The presiding priest was the zaotar- (OInd hótar-) ‘the one who offers libations,” who was attended by various functionaries. Another functional title, aθaurvan- (cf. OInd. átharvan-) became the name for the sacerdotal caste, though originally it may have designated those priests charged with the care of the sacred fire, ātar- (see ĀTAŠ), both the element and a deity. Worship of the deities was ritually performed through the yasna. Originally this was a complex ritual that involved the offering of a sacrifice (food) and the sacred haoma (drink). Modeled on rites of hospitality, the yasna was an elaborate festive meal to which a deity or deities were invited as honored guests. The deity was offered food and drink, and was entertained through the recitation of poetry created for the occasion to magnify the divine guest. The poet was called a mąθrān (cf. OInd. mantrín-), that is, one who creates sacred poetry (mąθra-). The yašts of the Avesta are collections of such poetry (see Thieme, 1957).

Beliefs about the soul, death, and an afterlife were complex. A person possessed a number of what one might loosely call souls. In addition to animating forces, the urvan (Pahl. ruwān) was the individual’s soul, which survived death and went to the other world; the frawaši was a guardian spirit; the daēnā was a sort of spiritual double (Gignoux, 2001, pp. 12-16, 20-30; Widengren, 1983). At death, when the breath of life (vyānā-; Mid. Pers. gyān, NPers. jān) departed, the soul hovered near the corpse (immediately possessed by Nasu, the demon of putrefaction) for three days before journeying to a bridge crossing to the other world. This is the Činwad bridge (see ČINWAD PUHL) mentioned already by Zarathustra. It is not known what ethical concepts were originally applied to this perilous crossing, but with Zarathustra and the rest of the Zoroastrian tradition the crossing meant the time of reckoning for one’s good and evil deeds, with the righteous proceeding to heaven, the wicked to the abyss.

Zarathustra. One of the most vexing problems for a history of Zoroastrianism is the location of Zarathustra in time and place. While there is general agreement that he did not live in western Iran, attempts to locate him in specific regions of eastern Iran, including Central Asia, remain tentative. Also uncertain are his dates. Plausible arguments place him anywhere from the 13th century BCE to just before the rise of the Achaemenid empire under Cyrus II the Great in the mid-6th century BCE, with the majority of scholars seeming to favor dates around 1000 BCE, which would place him as a contemporary, at least, of the later Vedic poets (see, e.g., Boyce, 1975-82, I, pp. 190-91; Duchesne-Guillemin, pp. 135-38; Gnoli, 1980, pp. 159-79; Henning; Hertel; Herzfeld; Jackson, 1896; Klima, 1959; Shahbazi, 1977 and 2002).

The milieu in which Zarathustra began his mission was sketched above. He was both a zaotar and a mąθrān. The only reliable biographical information about him is contained in his Gathas, preserved by oral tradition for centuries and then continued to the present in oral and written priestly transmission. Zarathustra had a particularly close relationship with Ahura Mazdā, from whom he received revelatory visions (daēnā-). His vision, expressed in the Gathas, included a radical transformation of traditional beliefs. In place of the pantheon he elevated Ahura Mazdā to a position of supremacy that approaches monotheism and surrounded him with a group of abstract entities, the Aməša Spəntas, all of whom perpetuate key concepts of Iranian religion as hypostases of Ahura Mazdā. At the heart of the vision, though, was an ethical dualism that saw the principles of Truth (aṧa-) and Falsehood (druj-, OPers drauga-, OInd. dróha-) in fundamental opposition. In Zarathustra’s thought dualism is not primordial, as it appears in later Sasanian theology, but arose out of the right and wrong choices made by twin Spirits, who stand in paradigmatic relationship to human beings in the exercise of free will. As a result, the world could be divided between the followers of Truth (aṧavan-, cf. OPers. artāvan-, OInd. ṛtāˊvan-) and the followers of the Lie (drugvant-; see DRUJ). His dualistic theology also included the polarization of the traditional classes of deities, the ahuras and the daēvas. As a zaotar, Zarathustra was concerned with proper cultic practice, especially the proscription of violence upon the sacrificial victim as carried out by the daēvic priests. He may have modified the haoma cult, but certainly did not ban it. Finally, Zarathustra articulated the kernel of the idea of a Savior figure, the Saošyant (Mid. Pers. Sōšyans), who would arrive in the future to redeem the world.

The history of Iranian religion after Zarathustra is very difficult to reconstruct. In the course of his ministry in eastern Iran, he converted a local ruler (kavi-) named Vištāspa, who became his patron and protector (Jackson, pp. 59 ff; Boyce, 1975-82, I, pp. 11, 279-81). For convenience, following Ilya Gershevitch (pp. 8-9), we may call the religion of the prophet “Zarathuštrianism.” We can only assume that the religious community that Zarathustra founded continued and thrived after his death. The Yasna Haptaŋhaitī is the production of this community. With the consolidation of greater Iran under the Achaemenids, his religion, into whatever form it had evolved, made its way to western Iran, where it encountered forms of Iranian religion different not only from itself, but also from non-Zarathuštrian religions of the East.

The Achaemenid period. The question of Zoroastrianism among the Medes is moot, as we possess too little information about this period to form any clear idea what their religious practices and beliefs were. The one piece of information that stands out is the inclusion of the Magi by Herodotus in a listing of the Median tribes (Herodotus, 1.101). The power that the Magi enjoyed in western Iran during the Median rule is indicated by further statements of Herodotus concerning the pervasive presence of this priesthood in religious matters. From Herodotus’s account we learn that the Magi were necessary for the performance of sacrifices at which they recited “theogonies,” that is, presumably hymns in praise of the gods being worshiped. They also were involved in the disposal of the dead through exposure to birds and dogs; and they exhibited a passion for killing noxious creatures (Herodotus, 1.132). Further the political intrigues of the Magi, especially that of the false Smerdis/Bardiya, attested both in Herodotus and Darius’s inscription at Bisotun (DB 1.30-33; Herodotus, 3.30, 61, 65 ff.), and the subsequent magophonia festival, bear witness to the continued importance of this caste in Pārsa and the Achaemenid empire (Herodotus, 3.78-79). As Zoroastrianism became the dominant religion of the empire, the Magi assumed its priestly functions, giving their name to the priestly nomenclature of post-Achaemenid Zoroastrianism.

There is no consensus among scholars over the question whether the early great kings (Cyrus II The Great, Darius I The Great, Xerxes) were influenced by some form of Zarathuštrianism. They certainly believed in the absolute supremacy of Ahura Mazdā (OPers. Auramazdāh-) and in the dichotomy of ahura- and daiva-. Beyond that, however, all is speculation. Neither the Achaemenids themselves nor Herodotus mention Zarathustra, and Gathic quotations, which some see in the inscriptions (Skjærvø, 1999) may merely reflect phrases common to the shared (Indo-)Iranian poetic diction. Although Cyrus’s famous cylinder inscription proclaiming himself as the appointee of the Babylonian deities may be dismissed as pure propaganda, it does stand in sharp contrast to the fervent devotion to Ahura Mazdā of Darius and Xerxes. The latter’s destruction of the daivadāna- (daiva-sanctuary; XPh 35-41) may show Zoroastrian zeal, or it may bear witness to an old Iranian dichotomy independent of the Prophet’s teachings. Centuries later, the Sasanians, who were indisputably Zoroastrians, in their inscriptions invoke Ohrmazd and use the term mazdēsn “Mazdean” (e.g., Šāpur I’s inscriptions ŠKZ 24, Ḥajjiābād [ŠH] 1, 3; Šāpur II at Ṭāq-e Bustān [ŠTBn] 2, 5; Narseh at Veh Šābuhr [NVŠ] 1, 6; see Back, pp. 334, 372, 490), nowhere did they mention the prophet’s name (*Zarduxšt). Achaemenid imperial art shows at least extensive iconographic borrowing from the ancient Near East, for example, the winged Ahura Mazdā icon borrowed from nearly identical Assur figures (Root, 1975; Jacobs, 1991). The silence of the sources may reflect the attitude of the Achaemenids toward religion in general. Their policy toward non-Iranian religions was one of tolerance and issues of orthodoxy at home, so prominent under the Sasanians, were probably not a concern to them.

In any case, the reign of Artaxerxes II (404-359 BCE), marked by a calendar reform, in which the names of Zoroastrian deities were substituted for the earlier Persian month-names, by the introduction of the Anāhitā cult and the worship of Mithra, and by the first mention of Zoroaster in Greek sources, was a turning point (see CALENDARS i.). What emerged during the Achaemenid period was an eclectic Iranian religion, Zoroastrianism, which contained elements of Zarathuštrianism, apocryphal legends of the prophet, a full pantheon of deities that are almost entirely absent from the Gathas, an overriding concern over purity and pollution, the establishment of fire temples, a strong ethical code based on man’s part in the cosmic struggle between the principles of the Truth and the Lie, and an eschatology which saw history as an unfolding struggle between these principles, which would lead to the final Renovation (frašō-kərəti) of the Cosmos. Thus, it contained a great deal of the Old Iranian religion outlined above. Curiously, the extant Avesta remains thoroughly eastern Iranian in its geographic (see AVESTAN GEOGRAPHY; Gnoli, 1980; idem, 1985, pp. 17-30) and linguistic orientation (see AVESTAN LANGUAGE). One assumes that radical concessions to traditional beliefs had already taken place after Zarathustra’s death and before Zoroastrianism became pan-Iranian.

A significant question, for which there are few definitive answers, is to what extent were Judaism and later Christianity indebted to Zoroastrianism for ideas that surfaced beginning in the 5th century BCE but persisted well into the Parthian period, ideas such as a trans-historical mašiaḥ, heaven and hell, and a day of judgement.

Greeks and Parthians. Our knowledge of Zoroastrianism during the long stretch of time extending from the conquest of the Persian empire by Alexander The Great (330, i.e., the death of Darius III) to the foundation of the Sasanian dynasty (ca. 224 CE) is very fragmentary. Although pieces of information are abundant enough to witness the presence of Zoroastrianism throughout the Near East, including Armenia, they do not add up to a coherent history. Sasanian writers knew of Alexander only as a legendary, evil (Mid. Pers. gizistag) Roman (hrōmāyig, i.e., Byzantine) enemy of Iran, who destroyed the Avesta and created general confusion of the Good Religion. There is a vague reference in the Dēnkard to an attempt under Walaxš (Vologases I, ca. 51-80; see BALĀŠ I) to gather together the Avesta dispersed because of Alexander. In general, however, Sasanian political rhetoric was at pains to place the Arsacids in a bad light as custodians of traditional Iranian values, while portraying themselves as the restorers of tradition and particularly of Zoroastrianism. Since already in the 3rd century the high priest Kirdēr presupposes an ecclesiastical hierarchy and organization, one may assume that this was an inheritance from the Arsacids (Widengren, 1965a).

The Sasanians (see also SASANIAN DYNASTY). The ancient world at the time of the Sasanian rise to power under Ardašir (ca. 224 CE) was very different from that which the Achaemenids had entered more than seven centuries before. The Roman empire extended throughout the Mediterranean world and had challenged the Parthians over control of the Near Eastern heartland. Although the Roman empire embraced and tolerated a vast array of local and national religions, the Roman Imperial Cult, soon to be replaced by Christianity, was imposed throughout the empire. Local religious movements and cults were gaining universal followings. Not only was the tide of Christianity rising in the west, but also the wave of Buddhism had been sweeping over eastern Iran and Central Asia. Jewish communities were long settled in Mesopotamia and Persia, and Manicheism was soon to burst on the scene. Zoroastrianism itself had been the national religion of the majority of Iranian peoples, whether they were living in the Near East or on the Iranian plateau. Whereas the Arsacids had continued the tradition, going back to the Achaemenids, of religious tolerance throughout their empire, the Sasanians broke with that practice. Also, while there can be no doubt that among the Arsacids and their predecessors the support and spread of Zoroastrian institutions was closely tied to the interests of the state, the Sasanians quickly developed a theology of the unity of church and state, which was generally intolerant both of foreign, that is, non-Zoroastrian, religions and of internal deviations from what would be declared orthodoxy. The Iranian example was to be followed in the west as Christianity became the state religion of the Roman empire(s), and, centuries later, the arrival of Islam through the Arab conquest would have a devastating effect upon Zoroastrianism itself.

The Sasanian period was one of relative stability, during which Zoroastrianism flourished. Although there were heresies and challenges from other religions, the authority of the Zoroastrian church was basically uncontested. The numbers of sacred fires were greatly increased throughout Persia and with them the pervasive presence of priests. There were calendar reforms and the standardization of the yearly cycle of festivals. Zoroastrianism also supported an increasingly rigorous division of society into castes (pēšag), with priests and nobles as elites lording it over peasants and artisans. The burden of support for the elites shouldered by the lower castes was heavy, and their plight would find brief expression in Mazdakism (see below).

Ardašir I Pāpagān (ca. 224-40), founder of the Sasanian dynasty, set about to establish uniformity in theology and practice throughout his empire. He was assisted in his project by an able hērbed named Tansar (or Tōsar). From Tansar’s own epistle, the Nāma-ye Tansar, preserved in a 13th-century Persian translation by Ebn Esfandiār of an Arabic translation, and from various notices in the Dēnkard, we know that he was responsible for two major policy moves. One was the establishment of a new canon of authoritative scriptures that was purged of materials judged heterodox. This new canon provided a basis for placing all interpretation of the religion within his control under a declaration of infallibility. The other was to promote the expansion of sacred fires while enforcing cultic uniformity. Especially important was the iconoclasm of the reformed Zoroastrianism, which forbade the use of idols in worship but allowed extensive use of divine images in art. In many cases the installation of the sacred fire was the substitute for a purged image (Boyce, Introd. to Nāma-ye Tansar, tr., pp. 5-7).

Ecclesiastical authority soon passed to an extraordinary priest named Kirdēr, whose long career began under Ardašir and extended into the reign of Bahrām II (r. 276-93). Even though Šāpur I (r. 240-72) speaks of the many fires which he established, he seems to have relaxed the policies of Ardašir and Tansar in matters of religion, allowing not only a free exercise of belief but also himself flirting with the new gnosticism preached by Māni at court. His long reign must have tried the patience of the strictly orthodox Kirdēr. Yet, the skilful priest maintained his power, while waiting for a change in succession. After the death of Šāpur, Kirdēr’s power grew greatly to the point that he was the supreme authority in all matters pertaining to religion. In fact, his power paralleled royal power to the extent that, uniquely, he could publish his inscription in various places, including the Kaʿba-ye Zardošt below the famous inscription of Šāpur I (see Gignoux, 1983, pp. 1209-11; idem, 1965; Hinz, 1970). From the first part of this inscription we learn that a formidable bureaucracy was in place to support the establishment and maintenance with funds and magi of local fires in both Iranian and non-Iranian territory. Further, heresies had been rooted out, idols destroyed, and other religions (inter al., Jews, Christians, Manicheans, Buddhists and Brahmins) were being attacked. Using a theme to be greatly elaborated toward the end of the Sasanian period in the book Ardā Wirāz nāmag, (see ARDĀ WĪRĀZ), the second part of the inscription describes an other-worldly journey by mediums conjured up by Kirdēr, whose mission it was to confirm his spiritual authority. (see SHAPUR I, sec. 4; Skjærvø, 1983).

It seems from Manichean sources that Kirdēr arranged to have Māni dispatched sometime during the reign of Bahrām I (Mary Boyce, 1975, texts m-p, pp. 43-48; Widengren, 1965b, pp. 37-42), and, while it flourished in other parts of the ancient world, Manicheism was rendered insignificant in the Iranian heartland. The most significant theological controversy within Zoroastrianism, one that seems to have been already present in the Parthian period and perhaps earlier, was over Zurvanism. This theology reckoned Zurvān “Time” as the supreme deity, whose twin sons, Ohrmazd and Ahriman, vied for control of the universe (Zaehner, 1955, pp. 60-61, 245). It was opposed to the dualistic theology that held Ohrmazd and Ahriman to be primordial, uncreated spirits. Although radical dualism prevailed in the latter part of the period, it is not clear to what extent Zurvanism was ever viewed as heresy. It is probable that Kirdēr himself held Zurvanite beliefs, and all evidence indicates that it was the accepted orthodox theology among the Sasanian rulers (see Boyce, 1979, pp. 112-13, 118-23). Šāpur II (r. 309-79), shortly after ascending the throne, assembled representatives of various religious movements, about whom no details are given, in order to establish truth. A certain priest named Ādurbād ī Mahraspandān prevailed, not only by theological argument, but also by submitting successfully to the ordeal (war) of having molten metal poured on his chest. As with Tansar, this was an occasion for the king to affirm orthodoxy and to root out heterodoxy. One may wonder whether this was a triumph of Zurvanism. It is possible, moreover, that the development of the Avestan script and organization of the religious canon into the Nasks (divisions) was carried out during the reign of Šāpur II, although it seems more likely that it was the achievement of Ḵosrow I Anōširavān (r. 531-79).

While wars with Rome and Byzantium in the west and skirmishes with nomadic tribes in the northeast were a perpetual threat to the stability of the empire, signs of internal social unrest were clearly visible during the reign of Kawād I (r. 488-531) with the rise to prominence of the religious-social movement led by a certain Mazdak ī Bāmdādān, who would displace Māni in the later literature as the arch-heretic. Mazdakism was an eclectic religion based in both Zoroastrianism and in an ascetic spirituality that appears to have roots in Manicheism. It challenged the establishment, preaching social equality, including women, to the extent that property should be held in common. The appeal of such ideas to the masses is obvious, yet Mazdakism also had a following among nobles. Kawād himself embraced Mazdakite ideas. For this apostasy he was deposed by a coalition of nobles and priests, only later to win back the throne. After that he distanced himself from Mazdakism to the extent that eventually he allowed his son, Ḵosrow I to have Mazdak and his followers killed at a banquet in 528 (see Klima, 1977; Yarshater; Nöldeke, Geschichte der Perser, pp. 455-67).

The reign of Ḵosrow I is remembered, often romantically, into the Islamic period as the great era of the blossoming of Sasanian culture and political power. This was not so much a time of innovation as that of consolidation and preservation. For Zoroastrianism this meant primarily the final canonization of the sacred Avesta together with its commentary traditions, the Zand, as well as the production of other forms of religious literature. The extensive Pahlavi writings of the 9th century are either copies of or, what is more significant, digests of the vast literature of late Sasanian times. After Ḵosrow’s death, internal struggles for power and the external defense of borders led to a fairly rapid decline in the central authority of the state (see HORMOZD IV; HORMOZD V). No one was aware of the assault on Zoroastrianism and on the state that was about to issue from Arabia.

When Yazdagird III perished in 651, Zoroastrianism was dealt a blow from which it never recovered, even though it has managed to survive to the present day. The military conquest of the Sasanian empire was relatively swift, the religious conquest slower, yet ultimately triumphant (see ʿARAB v.). The reasons for the triumph of Islam are complex. There were certain cases of conversion by the sword, but these were the exception. Rather, the motivations for Zoroastrian conversion must be sought elsewhere. A central problem for the survival of Zoroastrianism was Sasanian theology of the unity of throne and church. With the elimination of the throne, the church was not only bereft of its political-economical support, but also of its place in the eschatological plan of world history. The oppressed state of the lower classes in Sasanian society that had provided the conditions for the rise of Mazdak had remained unaddressed. Islam’s promise of universal equality must have given many people both spiritual and material hope for a better life. Furthermore, the relegation of Zoroastrians to the tolerated, though second-class status of “people of the book” (ahl al-ketāb) was a clear incentive for many who sought advancement to apostatize. In some ways Zoroastrianism was an archaic religious system with complex rituals that could be performed only by priests and with a dualistic theology that was wedded to ancient myths and ancient deities. In contrast, Islam presented a simple monotheistic theology that did not need to be mediated by an institutional priesthood. Moreover, because it held key beliefs in common with Zoroastrianism, especially that world history was leading to the Day of Judgement to be followed by eternal life of beatitude for the righteous, Islam presented a path to salvation that was familiar to Zoroastrians. Besides, as Islam became entrenched in Persia, it borrowed from Zoroastrianism; Shiʿites eventually held the idea of a future savior (the “Hidden Imam”), embraced shrines of saints, and developed a system of clergy. Islamic law also presented a comprehensive ethical system for the individual and society that could displace the ideals of Zoroastrianism.

In spite of the constant erosion of Zoroastrian influence in the early centuries of Arab/Islamic dominance, the Good Religion maintained a vigorous presence in Iranian society. From the point of view of later history, the 9th and early part of the 10th centuries were pivotal for the preservation of the faith, for that period witnessed a prodigious output of religious literature mentioned above. We cannot know to what extent this scholarly, intellectual activity was motivated by a premonition of impending eclipse or by hope for revival. What it did accomplish was the production of encyclopedias, treatises on ethics and ritual, theological tracts, and the provision for the scribal tradition that would preserve the written testimony of Zoroastrianism through great vicissitudes up to modern times.


The bibliography for pre-Islamic Zoroastrianism is vast. The works listed below are major works in the field (with brief annotations) or discussions of topics in the text above. Particularly important are the comprehensive volumes by M. Boyce (History)and M. Stausberg, the latter especially for its bibliography. For the general reader and for use in college courses, Boyce’s Zoroastrians provides an accessible orientation. See also the many specialized entries in EIr. (keyword search “Zoroastrian” at iranicaonline.org).

Michael Back, Die Sassanidischen Staatsinschriften: Studien zur Orthographie und Philologie des Mittelpersischen der Schriften, Acta Iranica 18, Leiden, 1978.

Harold W. Bailey, Zoroastrian Problems in the Ninth-Century Books, Oxford, 1943.

Emile Benveniste, “L’Ērān-vēž et l’origine légendaire des Iraniens,” BSOS 7, 1933-35, pp. 265-74.

Mary Boyce, A Reader in Manichaean Middle Persian and Parthian: Texts with Notes, Acta Iranica 9, Leiden, 1975.

Idem, Zoroastrians: Their Religious Beliefs and Practices, London, 1979 (basically a summary history of Zoroastrianism from its beginnings to the present intended for the general reader, following the contours of her three-volume history).

Idem, A History of Zoroastrianism, vols. I-II, Leiden, 1975-82. Mary Boyce and Franz Grenet A History of Zoroastrianism III: Zoroastrianism under Macedonian and Roman Rule, Leiden, 1991. (These three volumes present a comprehensive, detailed, and richly documented account of the beginning of Zoroastrianism, its development under the Achaemenids and during a long period extending from the Macedonian conquest of Persia in 330 BCE to the 4th century CE in the Greco-Roman cultural and political spheres. In the first volume, the author has used later Pahlavi sources, rather uncritically, to provide a reconstruction of Zoroaster’s religion. She also seeks to establish a very early date for Zoroaster and to demonstrate the great continuity of the belief and practice; some of her conclusions, however, have been argued against by other scholars of the field.)

Muhammad A. Dandamaev, A Political History of the Achaemenid Empire, tr. Willem J. Vogelsang, Leiden, 1989.

George Dumézil, Naissance d’archanges, Abbeville, 1945 (in a variety of books, but mainly in this one, the author describes Zarathustra’s theology of the Aməša Spəntas as a sublimation of his tripartite ideology of the Indo-Europeans).

Jean Duchesne-Guillemin, La religion de l’Iran ancien, Paris, 1962 (an excellent handbook; the author, although under the influence of George Dumézil’s theory of a tripartite ideology, is not intrusively dogmatic and presents a balanced view with references to various scholarly approaches).

Ebn Esfandiār, Nāma-ye Tansar, ed. Mojtabā Minovi, Tehran, 1975; tr. Mary Boyce as The Letter of Tansar,Rome, 1968.

Ilya Gershevitch The Avestan Hymn to Mithra, Cambridge, 1959 (tr. of Yašt 10 with commentary, with an introduction containing a cogent reconstruction of the development of the religion in which the terms “Zarathustrianism” and “Zoroastrianism” are defined to differentiate the religion of the prophet from the religion of the Younger Avesta).

Philippe Gignoux, “Middle Persian Inscriptions,” in Camb. Hist. Iran III/2, 1983, pp. 1205-15.

Idem, “L’Inscription de Kartir à Sar Mašhad,” JA 256, 1968, pp. 387-418.

Idem, Man and Cosmos in Ancient Iran, Rome, 2001.

Gherardo Gnoli, Zoroaster’s Time and Homeland: A Study on the Origins of Mazdeism and Related Problems, Naples, 1980.

Idem, De Zoroastre à Mani, Pais, 1985.

Idem, The Idea of Iran: An Essay on Its Origin, Rome, 1989.

Walter Bruno Henning, Zoroaster: Politician or Witchdoctor, Oxford, 1951 (harshly criticizes both Herzfeld and Nyberg).

Johannes Hertel, Die Zeit Zoroasters, Leipzig, 1924.

Ernst Herzfeld, “The Traditional Date of Zoroaster,” in Jal Dastur C. Parvy, ed., Oriental Studies in Honour of Cursetji Erachji Parvy, London, 1933, pp. 132-36.

Idem, Zoroaster and His World, 2 vols., Princeton, 1947 (portrays Zarathustra as a player at the Achaemenid court; criticized and refuted by Henning).

Walther Hinz, “Die Inschrift des Hohenpriesters Kardēr am Turn von Naqsh-e Rostam,” AMI, NS 3, 1970, pp. 251-65.

A. V. Williams Jackson, “On the Date of Zoroaster,” JAOS 17, 1896, pp. 1-22.

Bruno Jacobs “Der Sonnengott im Pantheon der Achämeniden,” in J. Kellens, ed., La religion iranienne à l’époque achéménide, Gent, 1991, pp. 58-80.

Jean Kellens Les textes vieil-avestiques I, text with Fr. tr. and commentary, Wiesbaden, 1988 (argues that Zarathustra never existed as an individual, and the work attributed to him was really by a committee of poets).

Otakar Klima, “The Date of Zoroaster,” Archiv Orientali 27, 1959, pp. 556-64.

Idem, Beiträge zur Geschichte des Mazdakismus, Prague, 1977.

Herman Lommel, Die Religion Zarathustrasnach dem Awesta dargestelt, Tübingen, 1930. (The problems involved in interpreting the Gathas and of reconstructing a coherent picture of Zoroaster’s religion still plague scholarship; yet this work of Lommel remains the most balanced account and necessary starting point for discussion. For details on Gathic problems see further under ZOROASTER and GATHAS.)

Henrik Samuel Nyberg, Die Religionen des alten Irans, tr. Hans Heinrich Schaeder, Leipzig, 1938; 2nd ed. with new Preface, Osnabrück, 1966 (presents Zarathustra as just a shaman; sharply criticized and refuted by Henning).

Margaret C. Root, The King and Kingship in Achaemenid Art, Leiden, 1975, pp. 169-176.

James Russell, Zoroastrianism in Armenia, Cambridge, Mass., 1987 (combines knowledge of Zoroastrianism and of Armenian sources to provide a comprehensive work on this often neglected area).

A. Shapur Shahbazi, “The Traditional Date of Zoroaster Explained,” BSOAS 40, 1977, pp. 25-35.

Idem, “Recent Speculations on the ‘Traditional Date of Zoroaster’,” Studia Iranica 31/1, 2002, pp. 7-45.

Michael Stausberg, Die Religion Zarathustras: Geschichte, Gegenwart, Rituale, 2 vols., Stuttgart, 2002. (The first volume provides an excellent detailed history of pre-Islamic Zoroastrianism with rich, up-to-date bibliography and much useful and necessary discussion of methodological problems; it is, however, not as comprehensive as Mary Boyce’s History.)

Martin Schwartz, “The Old Eastern Iranian Worldview According to the Avesta,” in Camb. Hist. Iran II, 1981, pp. 640-63 (an informative article about the cultural background of the Avesta).

Idem, “The Religion of Achaemenian Iran” in Camb. Hist. Iran II, pp. 664-97.

P. Oktor Skjærvø “Kirdir’s Vision,” AMI 16, 1983, pp. 269-306.

Idem, “Avestan Quotations in Old Persian,” in S. Shaked and A. Netzer, eds., Irano-Judaica IV, Jerusalem, 1999, pp. 1-64.

Paul Thieme “Vorzarathustrisches bei den Zarathustriern und bei Za rathustra,” ZDMG, 107, 1957, pp. 67-104.

Geo Widengren, Die Religionen Irans, Stuttgart, 1965a (an excellent handbook of the pre-Islamic religions of Iran, although the author was strongly influenced by Dumézil and by Nyberg’s shamanistic interpretation of Zarathustra; it makes the most use of the comparative religious method).

Idem, Mani und der Manichäismus, tr. Charles Kessler as Mani and Manichaeism, New York, Chicago, and San Francisco, 1965b.

Idem, “La recontre avec la daēnā, qui represente les actions de l’homme,” in Gherardo Gnoli, ed., Orientalia Romana: Essays and Lectures 5, Iranian Studies, Rome, 1983, pp. 41-79.

Ehsan Yarshater, “Mazdakism,” in Camb. Hist. Iran III/2, 1983, pp. 991-1024.

Robert C. Zaehner, Zurvan, A Zoroastrian Dilemma, Oxford, 1955.

Idem, The Dawn and Twilight of Zoroastrianism, London, 1961. (As the title suggests, this book basically ignores the Greco-Roman and Arsacid periods; Zaehner’s approach, although somewhat idiosyncratic and dogmatic, provides a balance to the weight of Dumézil’s and Nyberg’s theories, which were prevalent in the mid-twentieth century. The book also contains an annotated bibliography.)

(William W. Malandra)

Originally Published: July 20, 2005

Last Updated: July 20, 2005