Indo-Europeans and Their Origins
A long standing, and still unchallenged, belief of historians is that the people of Europe, Iran, and India, with the exception of Hungarians and the Finns, have their ancestry in common. Based on historical evidence and supports from archaeology, historians propose the existence of a pre-historic tribal confederation, called by scholars "the Indo-Europeans", who eventually spread out from their original homeland to cover the mass of land in western Eurasia. Their language and culture survived through that of their descendants, and it is based on comparative studies of various Indo-European languages and cultures that the idea of a common ancestry first came to existence.
Considerable amount of criticisms has been bestowed upon the idea of Indo-European ancestry. It has been called a racist idea, it has been challenged by those who felt "left-out" of it, and it has been linked to colonialism and the idea of European superiority. Probably the worst use of this theory has been the Nazi ideology of a pure "Aryan" race. Nevertheless, our purpose here is purely historical, and for the sake of the narrative, we assume that the idea of a common Indo-European ancestry, first and foremost in linguistic and mythological terms rather than biological, is valid and at least supportable.
One of the most serious problems for all adherents to the common ancestry theory is the location of the original homeland of Indo-Europeans. We know the historical residence of the descendants of Indo-Europeans stretches from Chinese Turkistan to the British Isles. It is exactly this vast territory that causes the most confusion and uncertainty in designating a “homeland” to the Proto-Indo-Europeans. From the early nineteenth century, different theories came to existence regarding this matter. Almost any land between Amur River and the Elbe has been taken up by one scholar or another as the original homeland. Among these, the most prominent theories are the ones that look for the Indo-European homeland in Steppes of northern Black Sea, and those who point to eastern Anatolia as the place for the homeland. The arguments of the latter, whose most prominent supporter is Colin Renfrew, are largely based on philology, which by itself can be quite misleading. The former argument, put forth initially by Marija Gimbutas, is based on archaeological findings and a fair amount of linguistic and mythological comparisons, and designates the people of the so-called “Kurgan” (pit-grave) culture of Don River basin as being the so-called Proto-Indo-Europeans
Due to the limitation of space in this article, I am forced to refer those more interested in the details of these theories to an excellent summary of all these arguments; a book by J.P. Mallory entitled “In Search of Indo-Europeans.” Out of all different theories, the present author is most inclined towards Prof. Mallory’s own “refined” version of Gimbutas’ theory. Mallory correctly points out that the limiting of the Proto-Indo-Europeans to the Don River basin causes practical problems for the explanation of their obvious later movements to the east of Caspian Sea and even further to the Amur River basin. He thus stretches the original homeland to include the western and northern shores of the Caspian. In Mallory’s view, the more easterly part of this “homeland” was where the ancestors of Indo-Iranians started their migrations from,
later to be found in the steppes of eastern Caspian and Transoxiana.

Indo-Iranians
The people who lived at the eastern edge of the original Indo-European homeland, later moved east and south to historical Transoxiana sometimes at the end of the Eneolithic Era. They belonged to a branch of Kurgan people who are called the "Andronovo Culture" by archaeologists, after a village near which one of their large cemeteries was found. These people, who probably called themselves Aryans, spread more to the south, into present day Afghanistan and Eastern Iran sometimes around 2000 BCE. There, they seem to have been split into two branches, the eastern one called Indo-Aryans by historians, and the other Proto-Iranians, on the west. Much of the information we have of the division between these two groups comes from their later epic and religious literature (RgVeda’s and the Avesta repectively), that showes a fascinating and very similar social structure for both of these groups. They were nomadic and had domesticated horses, probably as early as their time in the Steppes, and they had a complex pantheon of gods and natural forces. It has been suggested that prior to the first phase of their migration, Indo-Iranians have had a communal social system, but by the time of their split, they had formed into a patriarchal class system society. These changes, along with their complex belief system, lead some to believe that the proto-Indo-Iranian society was not as simplistic and nomadic based as currently assumed.
The split of proto-Indo-Iranians to Indo-Aryans and proto-Iranians happened at the dawn of history, ca. 2000-1800 BC. Indo-Aryans apparently moved to the Indus Valley region, with which they might have been familiar by their contacts with BMAC traders. There they faced the challenge of an established civilisation. The traditional story would tell us that the superior military power of Indo-Aryans, especially their use of horses, left no chance for the local Dravidians, who were conquered, massacred, and absorbed into the Aryan society as "untouchables" or driven to the south of the Indian peninsula. However, new studies whose scope is out of the capacity of the present paper, suggest that the conquest of the Harrappan culture and the establishment of an Indo-Aryan lead society did not happen as easily and took more time and included a higher degree of influence from the Dravidians on conquering Aryans, as apparent in the later Indian epics of Vedas and Mahabharata.
We have less evidence of such sudden conflict in the Iranian case. Proto-Iranians seem to have been split into branches early in their history, forming the nomadic Saka/Scythian tribes, and the settled populations that inhabited the Iranian plateau and eventually came to be known under the massive and inaccurate names of Parthians, Persians, and Medians. How early this split happened, and how the Iranians came to overpower the established civilisations of the Mitanni, the Kassites, and civilisations of eastern Iran, is not known. Only their final pressure in replacing the prosperous civilisation of Elam has survived into history. For earlier events, we only have scattered reports from the Assyrian and Babylonian chronicles, and rarely in Elamite reports.

One of the artefacts found from BMAC (courtsey MET)
Some Problems with the Indo-Iranian Prehistory
The idea of a simple split of Proto-Iranians from Indo-Aryans and especially their origin in Central Asia poses some problems. In dates prior to their widely accepted migration, we have evidence of their existence in Western Iran. Clear Indo-Aryan terms exist in a Mitanni manual for horse breeding, presenting us with the problem of having Indo-Aryan influence far the west of Iranians, instead of to their east. We know that horses were taken by Kassites to Babylon, and they most likely learned of horse taming from Proto-Iranians who lived to their east and north. Also, the names of Indo-Aryan deities like Indra, Mitra and the Nassaties exist among the names of Mitanni deities in a treaty with the Hittites, while these deities don't exist among the Iranian pantheon. Also, some Mitanni names have obvious Indo-Iranian and even purely Iranian overtones, while an Egyptian pharaoh married a girl from "east of Sumer" ca. 2200 BCE who has an Iranian name. As we can see, the route and time of Indo-Iranian migrations is not certain and provable, and some even deny any migration in a sensible term, and instead propose the gradual push of Indo-Iranians from the northern Caspian regions, via both Caucasus and Central Asia, in a much earlier (e.g. 3000 BCE) date.
Nevertheless, by 1200 BCE, we have a remarkable and undeniable Iranian presence in the plateau, and their overwhelming military force posed threats to the established civilisations of Assyria, Babylonia, and Elam. The early Iranian petty kingdoms seem to have established confederacies of all the tribes, Aryan and non-Aryan, and spread their early influence in the areas east of Elam. The earliest of these confederacies to form a coherent kingdom of which we have historical evidence was the kingdom of the Medes. We shall see the development of this kingdom in further chapters.
Refrences
Gimbutas, Marija A. The Kurgan Culture and the Indo-Europeanization of Europe: Selected Articles Form 1952 to 1993. American School of Classical Studies, 1997
Mallory, J.P. In Search of Indo-Europeans. Thames & Hudson; 1991
Mallory, J. P. “Archaeological models and Asian Indo-Europeans”, in Nicholas Sims-Williams ed. Indo-Iranian Languages and Peoples, Oxford University Press, 2002
Renfrew, Colin. Archaeology and Language : The Puzzle of Indo-European Origins. Cambridge University Press; 1990
Sims-Williams, Nicholas ed. Indo-Iranian Languages and Peoples, Oxford University Press, 2002
Sulimirski, T. “The Scyths”, in Ilia Gershevitch ed. Cambridge History of Iran Cambridge University Press, 1985
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