

Geographical extent of Iranian influence in the 1st century BCE.
The Parthian Empire (mostly Western Iranian) is shown in red, other areas, dominated by Scythia (Eastern Iranian), in orange.

Modern Iranian languages map

The language referred to as Proto-Indo-European (PIE): is ancestral to Diba and the Celtic, Italic (including Romance), Germanic, Baltic, Slavic, Indo-Iranian, Albanian, Armenian, Greek, and Tocharian languages.
There is an agreement that the PIE community split into two major groups from its homeland. One headed west for Europe and became speakers of Indo-European (all the languages of modern Europe save for Basque, Hungarian, Estonian, and Finnish) while others headed east for Eurasia to become Indo-Iranians.
The Iranian languages form a sub-branch of the Indo-Iranian sub-family, which is a branch of the family of Indo-European languages. Having descended from the Proto-Indo-Iranians, the Proto-Iranians separated from the Indo-Aryans early in the 2nd millennium BCE. The Proto-Iranians are traced to the Bactria–Margiana Archaeological Complex, a Bronze Age culture of Central Asia. The area between Afghanistan and the Aral Sea is hypothesized to have been the region in which the Proto-Iranians first emerged, following the separation of Indo-Aryan tribes.
The separation of Indo-Aryans proper from Indo-Iranians is commonly dated, on linguistic grounds, to roughly 1800 BCE. The Nuristani languages probably split in such early times, and are classified as either remote Indo-Aryan dialects or as an independent branch of Indo-Iranian. By the mid 2nd millennium BCE early Indo-Aryans had reached Assyria in the west (the Indo-Aryan superstrate in Mitanni) and the northern Punjab in the east (the Rigvedic tribes).
Some theonyms, proper names and other terminology of the Mitanni exhibit an Indo-Aryan superstrate, suggesting that an Indo-Aryan elite imposed itself over the Hurrian population in the course of the Indo-Aryan expansion.
In a treaty between the Hittites and the Mitanni (between Suppiluliuma and Matiwaza, ca. 1380 BCE), the deities Mitra, Varuna, Indra, and Nasatya (Ashvins) are invoked. Kikkuli’s horse training text (circa 1400 BCE) includes technical terms such as aika (eka, one), tera (tri, three), panza (pancha, five), satta (sapta, seven), na (nava, nine), vartana (vartana, round). The numeral aika “one” is of particular importance because it places the superstrate in the vicinity of Indo-Aryan proper as opposed to Indo-Iranian or early Iranian (which has “aiva”) in general.
Another text has babru(-nnu) (babhru, brown), parita(-nnu) (palita, grey), and pinkara(-nnu) (pingala, red). Their chief festival was the celebration of the solstice (vishuva) which was common in most cultures in the ancient world. The Mitanni warriors were called marya (Hurrian: maria-nnu), the term for (young) warrior in Sanskrit as well; note mišta-nnu (= miẓḍha,~ Sanskrit mīḍha) “payment (for catching a fugitive)” (Mayrhofer II 358).
The spread of Indo-Aryan languages has been connected with the spread of the chariot in the first half of the 2nd millennium BCE. Some scholars trace the Indo-Aryans (both Indo-Aryans and European Aryans) back to the Andronovo culture (2nd millennium BCE). Other scholars[8] have argued that the Andronovo culture proper formed too late to be associated with the Indo-Aryans of India, and that no actual traces of the Andronovo culture (e.g. warrior burials or timber-frame materials) have been found in India and Southern countries like Sri Lanka and the Maldives.[9]
Archaeologist J.P. Mallory (1998) finds it “extraordinarily difficult to make a case for expansions from this northern region to northern India” and remarks that the proposed migration routes “only [get] the Indo-Iranian to Central Asia, but not as far as the seats of the Medes, Persians or Indo-Aryans” (Mallory 1998; Bryant 2001: 216). Therefore he prefers to derive the Indo-Aryans from the intermediate stage of the Bactria–Margiana Archaeological Complex (BMAC) culture, in terms of a “Kulturkugel” model of expansion.
Likewise, Asko Parpola (1988) connects the Indo-Aryans to the BMAC. But although horses were known to the Indo-Aryans, evidence for their presence in the form of horse bones is missing in the BMAC. Parpola (1988) has argued that the Dasas were the “carriers of the Bronze Age culture of Greater Iran” living in the BMAC and that the forts with circular walls destroyed by the Indo-Aryans were actually located in the BMAC.
Parpola (1999) elaborates the model and has “Proto-Rigvedic” Indo-Aryans intrude the BMAC around 1700 BCE. He assumes early Indo-Aryan presence in the Late Harappan horizon from about 1900 BCE, and “Proto-Rigvedic” (Proto-Dardic) intrusion to the Punjab as corresponding to the Swat culture from about 1700 BCE.
Recently Leo Klejn proposed a hypothesis of linking the earliest stage of Indo-Aryan peoples with the Catacomb culture. The linguistic composition of the Catacomb culture is unclear. Within the context of the Kurgan hypothesis expounded by Marija Gimbutas, an Indo-European component is hard to deny, particularly in the later stages. Placing the ancestors of the Greek, Armenian and Paleo-Balkan dialects here is tempting, as it would neatly explain certain shared features.
More recently, the Ukrainian archaeologist V. Kulbaka has argued that the Late Yamna cultures of ca. 3200–2800 BC, esp. the Budzhak, Starosilsk, and Novotitarovka groups, might represent the Greek-Armenian-“Aryan”(=Indo-Iranian) ancestors (Graeco-Aryan, Graeco-Armenian), and the Catacomb culture that of the “unified” (to ca. 2500 BC) and then “differentiated” Indo-Iranians.
Grigoryev’s (1998) version of the Armenian hypothesis connects Catacomb culture with Indo-Aryans, because catacomb burial ritual had roots in South-Western Turkmenistan from the early 4th millennium (Parkhai cemetery). The same opinion is supported by Leo Klejn in his various publications.
The Indo-Iranians were a community that spoke a common language prior to their branching off into the Iranian and Indo-Aryan languages. Iranian refers to the languages of Iran (Iranian), Pakistan (Balochi and Pashto), Afghanistan (Pashto and Dari), and Tadjikistan (Tajiki) and Indo-Aryan, Sanskrit, Urdu and its many related languages.
By the early 1st millennium, Ancient Iranian peoples such as Medes, Persians, Bactrians, Parthians and Scythians populated the Iranian plateau, and other Scythian tribes, along with Cimmerians, Sarmatians and Alans populated the steppes north of the Black Sea. The Saka, Scythian, tribes spread as far west as the Balkans and as far east as Xinjiang.
Scythians formed the Indo-Scythian Empire, and Bactrians formed a Greco-Bactrian Kingdom founded by Diodotus I, the satrap of Bactria. The Kushan Empire, with Bactrian roots/connections, once controlled much of Pakistan, some of Afghanistan and Tajikistan. The Kushan elite (who the Chinese called the Yuezhi) were either a Tocharian-speaking (another Indo-European branch) people or an Eastern Iranian language-speaking people.
The division into an “Eastern” and a “Western” group by the early 1st millennium is visible in Avestan vs. Old Persian, the two oldest known Iranian languages. The Old Avestan texts known as the Gathas are believed to have been composed by Zoroaster, the founder of Zoroastrianism, with the Yaz culture (c. 1500–1100 BCE) as a candidate for the development of Eastern Iranian culture. Old Persian appears to have been established in written form by 519 BCE, following the creation of the Old Persian script, inspired by the cuneiform script of the Assyrians.
The language of the Medes, the Median language (also Medean or Medic), is an Old Iranian language and classified as belonging to the northwestern Iranian subfamily which includes many other languages such as Azari, Zazaki, Laki, Gorani, Gilaki, Mazandarani, Kurdish, and Baluchi.
is only attested by numerous loanwords in Old Persian. Nothing is known of its grammar, “but it shares important phonological isoglosses with Avestan, rather than Old Persian. No documents dating to Median times have been preserved, and it is not known what script these texts might have been in. The Median element is readily identifiable because it did not share in the developments that were particular to Old Persian. Remnants of the Median language and Old Persian show their common Proto-Iranian roots
A distinction from other ethno-linguistic groups (such as the Persians) is evident primarily in foreign sources, for instance from mid-9th century BCE Assyrian cuneiform sources and from Herodotus’ mid-5th century BCE second-hand account of the Perso-Median conflict. It is not known what the native name of the Median language was (this is also true for all other Old Iranian languages), or whether the Medes themselves nominally distinguished it from the languages of other Iranian peoples.
The original population area of the Median people was western Iran and named after them as “Media”. At the end of the 2nd millennium BCE the Median tribes emerged in the region (one of several Iranian tribes to do so) which they later called Media. These tribes expanded their control over larger areas subsequently, and, over a period of several hundred years, the boundaries of Media moved.
An early description of the territory of Media by the Assyrians dates from the end of the 9th century BCE until the beginning of the 7th century BCE. The southern border of Media, in that period, is named as the Elamite region of Simaški in present day Lorestan. From the west and northwest it was bounded by the Zagros mountains and from the east by Dasht-e Kavir. The region of Media was ruled by the Assyrians and for them the region “extended along the Great Khorasan Road from just east of Harhar to Alwand, and probably beyond. It was limited on the north by the non Iranian state of Mannea, on the south by Ellipi.” The location of Harhar is suggested to be “the central or eastern” Mahidasht in Kermanshah province.
The materials found at Tepe Nush-i Jan, Godin Tepe, and other sites located in Media together with the Assyrian reliefs show the existence of urban settlements in Media in the first half of the 1st millennium BCE which had functioned as centres for production of handicraft and also of an agricultural and cattle-breeding economy of a secondary type.
For other historical documentation, the archaeological evidence, though rare, together with cuneiform records by Assyrian make it possible, regardless of Herodotus accounts, to establish some of the early history of Medians.
Iranian tribes were present in western and northwestern Iran at least from 12th or 11th century BCE. The significance of Iranian elements in these regions were established from beginning of the second half of the 8th century BCE. By this time the Iranian tribes were the majority in what later become the territory of Median kingdom and also the west of Media proper.
A study of textual sources from the region show that in Neo-Assyrian period, the regions of Media and further west and northwest had a population with Iranian speaking people as majority.
In western and northwestern Iran and in areas west to these and prior to the Median rule there were previously political activities of powerful societies of Elam, Mannaea, Assyria and Urartu (Armenia).
There are various and up-dated opinions on the positions and activities of Iranian tribes in these societies and prior to the “major Iranian state formations” in the late 7th century BCE.
During the 1st centuries of the first millennium BCE, the ancient Persians established themselves in the western portion of the Iranian plateau and appear to have interacted considerably with the Elamites and Babylonians, while the Medes also entered in contact with the Assyrians.
During the period of the Neo Assyrian Empire (911-612 BC) the Medes, Persians and other Iranian peoples of northern and western Iran were subject to Assyria. This changed during the reign of Cyaxares, who in alliance with Nabopolassar of Babylon and the Scythians attacked and destroyed the strife riven empire between 616 and 605 BC.
Following the establishment of the Achaemenid Empire, the Persian language (referred to as “Farsi” in Persian) spread from Pars or Fars Province to various regions of the Empire, with the modern dialects of Iran, Afghanistan (also known as Dari) and Central-Asia (known as Tajiki) descending from Old Persian.
Old Persian is attested in the Behistun Inscription (c. 519 BCE), recording a proclamation by Darius the Great. In southwestern Iran, the Achaemenid kings usually wrote their inscriptions in trilingual form (Elamite, Babylonian and Old Persian) while elsewhere other languages were used. The administrative languages were Elamite in the early period, and later Imperial Aramaic.
The early inhabitants of the Achaemenid Empire appear to have adopted the religion of Zoroastrianism. The Baloch who speak a west Iranian language relate an oral tradition regarding their migration from Aleppo, Syria around the year 1000 CE, whereas linguistic evidence links Balochi to Kurmanji, Soranî, Gorani and Zazaki.
Indo-Aryans
Indo-Iranians
Iranian peoples
Iranian plateau
List of Ancient Iranian peoples
Indo-Aryan migration