http://en.wikipedia.org/wiki/Zoroaster
Until the late 1600s, Zoroaster was generally dated to about the sixth century BCE, which coincided with both the “Traditional date” (see details below) and historiographic accounts (Ammianus Marcellinus xxiii.6.32, fourth c. CE). However, already at the time (late nineteenth century), the issue was far from settled, with James Darmesteter pleading for a later date (c. 100 BCE) and others pleading for dates as early as 6000 BCE.[e]
The “Traditional date” originates in the period immediately following Alexander’s conquest of the Achaemenid Empire in 330 BCE. The Seleucid kings who gained power following Alexander’s death instituted an “Age of Alexander” as the new calendrical epoch. This did not appeal to the Zoroastrian priesthood who then attempted to establish an “Age of Zoroaster.” To do so, they needed to establish when Zoroaster had lived, which they accomplished by counting back the length of successive generations[6] until they concluded that Zoroaster must have lived “258 years before Alexander.” This estimate then re-appeared in the ninth- to twelfth-century texts of Zoroastrian tradition,[c] which in turn gave the date doctrinal legitimacy. In the early part of the twentieth century, this remained the accepted date (subject to the uncertainties of the ‘Age of Alexander’[d]) for a number of reputable scholars, among them Hasan Taqizadeh, a recognized authority on the various Iranian calendars and hence became the date cited by Henning and others.
By the late nineteenth century, scholars such as Bartholomea and Christensen noted problems with the “Traditional date,” namely in the linguistic difficulties that it presented. Since the Old Avestan language of Gathas (that are attributed to the prophet himself) is still very close to the Sanskrit of the Rigveda, it seemed implausible that the Gathas and Rigveda could be more than a few centuries apart, suggesting a date for the oldest surviving portions of the Avesta of roughly the 11th to 10th century BCE.
This 11th/10th century BCE date is now widely accepted among Iranists, who in recent decades found that the social customs described in the Gāthās roughly coincides with what is known of other pre-historical peoples of that period. Supported by this historical evidence, the “Traditional date” can be conclusively ruled out, and the discreditation can to some extent be supported by the texts themselves: The Gathas describe a society of bipartite (priests and herdsmen/farmers) nomadic pastoralists with tribal structures organized at most as small kingdoms. This contrasts sharply with the view of Zoroaster having lived in an empire, at which time society is attested to have had a tripartite structure (nobility/soldiers, priests, and farmers).
Although a slightly earlier date (a century or two) has been proposed on the grounds that the texts do not reflect the migration onto the Iranian Plateau, it is also possible that Zoroaster lived in one of the rural societies that remained where they were.
[edit] Place
Zoroaster; portrayed here in a popular Parsi Zoroastrian depiction. This iconographic tradition can be traced to the eighteenth century.Yasna 9 & 17 cite the Ditya River in Airyanem Vaējah (Middle Persian Ērān Wēj) as Zoroaster’s home and the scene of his first appearance. Nowhere in the Avesta (both Old and Younger portions) is there a mention of the Achaemenids or of any West Iranian tribes such as the Medes, Persians, or even Parthians.
However, in Yasna 59.18, the zaraθuštrotema, or supreme head of the Zoroastrian priesthood, is said to reside in ‘Ragha’. In the ninth to twelfth century Middle Persian texts of Zoroastrian tradition, this ‘Ragha’ – along with many other places – appear as locations in Western Iran. While Medea does not figure at all in the Avesta (the westernmost location noted in scripture is Arachosia), the Būndahišn, or “Primordial Creation,” (20.32 and 24.15) puts Ragha in Medea (medieval Rai). However, in Avestan, Ragha is simply a toponym meaning “plain, hillside.”[7].
Apart from these indications in Middle Persian sources which are open to interpretations, there are a number of other sources. The Greek and Latin sources are divided on the birth place of Zarathustra. There are many Greek accounts of Zarathustra, referred usually as Persian or Perso-Median Zoroaster. Moreover they have the suggestion that there has been more than one Zoroaster.[8] On the other hand in post-Islamic sources Shahrastani (1086-1153) an Iranian writer originally from Shahristān, present-day Turkmenistan, proposed that Zoroaster’s father was from Atropatene (also in Medea) and his mother was from Rai. Coming from a reputed scholar of religions, this was a serious blow for the various regions who all claimed that Zoroaster originated from their homelands, some of which then decided that Zoroaster must then have then been buried in their regions or composed his Gathas there or preached there.[9][10] Also Arabic sources of the same period and the same region of historical Persia consider Azerbaijan as the birth place of Zarathustra.[11]
By the late twentieth century the consensus amont some scholars had settled on an origin in Eastern Iran and/or Central Asia (to include present-day Afghanistan): Gnoli proposed Sistan (though in a much wider scope than the present-day province) as the homeland of Zoroastrianism; Frye voted for Bactria and Chorasmia;[12] Khlopin suggests the Tedzen Delta in present-day Turkmenistan.[13] Sarianidi considered the BMAC region as “the native land of the Zoroastrians and, probably, of Zoroaster himself.”[14] Boyce includes the steppes of the former Soviet republics.[15] The medieval “from Media” hypothesis is no longer taken seriously, and Zaehner has even suggested that this was a Magi-mediated issue to garner legitimacy, but this has been likewise rejected by Gershevitch and others.
The 2005 Encyclopedia Iranica article on the history of Zoroastrianism summarizes the issue with “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.”[16]