The period covered by the term Ancient Iran spans 12 centuries, from about 600 B.C. to about A.D. 600 -- approximately the date of the advent of Islam. Before that historical time period, there is cosmological time. Myths about the formation of the universe and legend about the founding kings of Iran define this era; after A.D. 600, Muslim writers wrote in a format we are familiar with as history. Historians can deduce facts about the ancient time period, but with caution, because many of the sources for the history of the Persian Empire are (1) not contemporary (so they are not eyewitnesses), (2) biased or (3) subject to other caveats. Here is more detail about the issues facing someone trying to read critically about or write a paper on Ancient Iranian history.
It is clear that histories in the sense of a history of Greece, Rome, much less of France or England, cannot be written about ancient Iran; rather, a short sketch of ancient Iranian civilization, including art and archaeology as well as other fields, must be substituted in many periods. Nonetheless an attempt is made here to utilize many works for a composite picture of the past, based on available sources."
Richard N. Frye The Heritage of Persia
Persian or Iranian?
Not an issue of reliability, but to offset any confusion you might have, the following is a quick look at two key terms.
Historical linguists and other scholars can make educated guesses about the origins of the Iranian people largely on the basis of the spread of language from a general expanse in central Eurasia. [See Tribes of the Steppe.] It is theorized that in this area, there lived Indo-European nomadic tribes who migrated. Some branched off into the Indo-Aryan (where Aryan seems to mean something like noble) and these split into the Indians and the Iranians.
There were many tribes among these Iranians, including those who lived in Fars/Pars. The tribe the Greeks first came into contact with they called Persians. Greeks applied the name to others of the Iranian group and today we commonly use this designation. This isn't unique to the Greeks: Romans applied the label Germanic to a variety of northern tribes. In the case of the Greeks and Persia, however, the Greeks have a myth deriving the Persians from their own hero, Perseus' offspring. Perhaps the Greeks had a vested interest in the label. If you read classical history, you will probably see Persian as the label. If you study Persian history to any extent, you will probably quickly see the term Iranian used where you might have expected Persian.
This is an issue you could face, if not in ancient Persian history, then in other areas of study of the ancient world.
It is unlikely that you will know all, or even one of the variations of the historic Iranian languages in which you will find textual evidence, so you will probably have to rely on translation. Translation is interpretation. A good translator is a good interpreter, but still an interpreter, complete with contemporary, or at least, more modern biases. Translators also vary in ability, so you may have to rely on a less than stellar interpretation. Using a translation also means you will not actually be using the written primary sources.
Non-Historical Writing - Religious and Mythical
The start of the historical period of ancient Iran roughly coincides with the coming of Zarathustra (Zoroaster). The new religion of Zoroastrianism gradually supplanted the existing Mazdian beliefs. The Mazdians had cosmological stories about the history of the world and the universe, including the coming of mankind, but they are stories, not attempts at scientific history. They cover a period that might be designated Iranian pre-history or cosmological history, a period of 12,000 mythological years.
We have access to them in the form of religious documents (e.g., hymns), written down centuries later, beginning with the Sassanid period. By Sassanid Dynasty we mean the final set of Iranian rulers before Iran was converted to Islam.
The subject matter of books like the 4th century A.D. scriptural writing (Yasna, Khorda Avesta, Visperad, Vendidad, and Fragments) in the Avestan language, and later, in Pahlavi, or Middle Persian, was religious. The important 10th century Ferdowsi's The Epic of Shahnameh was mythological. Such non-historical writing includes mythological events and the connection between legendary figures and the divine hierarchy. While this might not help too much with a terrestrial timeline, for the social structure of the ancient Iranians, it is helpful, since there are parallels between the human and cosmic world; for instance, the ruling hierarchy among the Mazdian deities is reflected in the king-of-kings overlording lesser kings and satrapies.
Archaeology and Artifacts
With the presumed real, historical prophet Zoroaster (whose exact dates are unknown), came the Achaemenid Dynasty, an historical family of kings that ended with Alexander the Great's conquest. We know about the Achaemenids from artifacts, like monuments, cylinder seals, inscriptions, and coins. Written in Old Persian, Elamite, and Babylonian, the Behistun Inscription (c.520 B.C.) provides Darius the Great's autobiography and narrative about the Achaemenids.
The criteria generally used for deciding on the value of historical records is:
- Are they authentic?
- Are the providers of the testimony eyewitnesses?
- Are they unbiased?
Archaeologists, art historians, historical linguists, epigraphers, numismatists, and other scholars find and evaluate ancient historical treasures, especially for authenticity -- forgery being an ongoing problem. Such artifacts can constitute contemporary, eyewitness records. They may allow dating of events and a glimpse into the everyday life of people. Stone inscriptions and coins issued by monarchs, like the Behistun Inscription, may be authentic, eyewitness, and about real events; however, they are written as propaganda, and so, are biased. That isn't all bad. In itself, it shows what is important to the boasting officials.
We also know about the Achaemenid Dynasty because it came into conflict with the Greek world. It was with these monarchs that the city-states of Greece waged the Greco-Persian Wars. Greek historical writers Xenophon and Herodotus describe Persia, but again, with bias, since they were on the side of the Greeks against the Persian. This has a specific technical term, "hellenocentricity," used by Simon Hornblower in his 1994 chapter on Persia in the sixth volume of The Cambridge Ancient History. Their advantage is that they are contemporary with part of Persian history and they describe aspects of daily and social life not found elsewhere. Both probably spent time in Persia, so they have some claim to being eyewitnesses, but not of most of the material about ancient Persia that they write.
In addition to the Greek (and, later, Roman; e.g., Ammianus Marcellinus) historical writers, there are Iranian ones, but they don't begin until late (with the coming of the Muslims), the most important of which are the tenth century compilations based mainly on anecdotes, Annals of al-Tabari, in Arabic, and the work mentioned above, The Epic of Shahnameh or Book of Kings of Firdawsi, in new Persian [source: Rubin, Ze'ev. "The Sasanid monarchy." The Cambridge Ancient History: Late Antiquity: Empire and Successors, A.D. 425-600. Eds. Averil Cameron, Bryan Ward-Perkins and Michael Whitby. Cambridge University Press, 2000]. Not only were they not contemporary, but they were not substantially less biased than the Greeks had been, since the beliefs of the Zoroastrian Iranians were at odds with the new religion.
- A Pocket Guide to Writing in History, by Mary Lynn Rampolla; 5th ed., St. Martin's: 2003.
- The Heritage of Persia, by Richard N. Frye.
- Mazdian Cosmology, by Iraj Bashiri; 2003
- Empires of the Silk Road, by C. I. Beckwith
- "Δον̑λος τον̑ βασιλέως: The Politics of Translation," by Anna Missiou; The Classical Quarterly, New Series, Vol. 43, No. 2 (1993), pp. 377-391.
- The Cambridge History of Iran Volume 3 Part 2: "The Seleucid, Parthian and Sasanian Periods" Chapter 37: "Sources of Parthian and Sasanian History, by G. Widengren; 1983
Herodotus Histories Book I. Macauley Translation