It has been suggested that the introduction of gray and gray-black pottery into western Iran from the northeast, which signals the start of the Iron Age, is the archaeological manifestation of this pattern of a gradual movement of Iranians from east to west. The case is by no means proved, but it is a reasonable reading of the combined evidence. If it is so, then the earliest Iranians in the Zagros Mountains can be dated to Iron Age I times, about 1300 bc. Archaeologically, the culture of Iron Age II times can be seen as having evolved out of that of the Iron Age I period, and, though the development is less clear, the same can be said of the relationship between the cultures of Iron Age II and III. The spread of the Iron Age I and II cultures in the Zagros is restricted and would appear to correspond fairly well with the distribution of Iranians known from the written documents. The distribution of the Iron Age III culture, on the other hand, is, at least by the 7th century bc, much more widespread and covers almost the whole of the Zagros. Thus, the argument that links these archaeological patterns with the Iranian migration into the area associates the Iron Age I and II cultures with the early penetration of the Iranians into the more eastern Zagros and with their infiltration westward along the major routes crosscutting the main mountain alignments. Those areas where traces of the Iron Age I and II cultures do not appear were the regions still under the control of non-Iranian indigenous groups supported by Urartu, Assyria, and Elam. The widespread Iron Age III culture is then associated with the rise to power of the Median kingdom in the 7th and early 6th centuries bc and the Iranianization of the whole of the Zagros Mountains. The kingdom of the Medes
Traditionally, the creator of the Median kingdom was one Deioces, who, according to Herodotus, reigned from 728 to 675 bc and founded the Median capital Ecbatana (modern Hamadān). Attempts have been made to associate Dāiukku, a local Zagros king mentioned in a cuneiform text as one of the captives deported to Assyria by Sargon II in 714 bc, with the Deioces of Herodotus, but such an association is highly unlikely. To judge from the Assyrian sources, no Median kingdom such as Herodotus describes for the reign of Deioces existed in the early 7th century bc; at best, he is reporting a Median legend of the founding of their kingdom.
According to Herodotus, Deioces was succeeded by his son Phraortes (reigned 675–653 bc), who subjugated the Persians and lost his life in a premature attack against the Assyrians. Some of this tale may be true. Assyrian texts speak of a Kashtariti as the leader of a conglomerate group of Medes, Scythians, Mannaeans, and miscellaneous other local Zagros peoples that seriously threatened the peace of Assyria’s eastern borderlands during the reign of Esarhaddon (680–669 bc). It is possible that Phraortes is this Kashtariti, though the suggestion cannot be proved either historically or linguistically. That a Median king in this period exerted political and military control over the Persians is entirely reasonable, though it cannot be proved.
Beginning as early as the 9th century bc and with increasing impact in the late 8th and early 7th centuries, groups of nomadic warriors entered western Iran, probably from across the Caucasus. Dominant among these groups were the Scythians, and their entrance into the affairs of the western plateau during the 7th century may perhaps mark one of the turning points in Iron Age history. Herodotus speaks in some detail of a period of Scythian domination, the so-called Scythian interregnum in Median dynasty history. His dating of this event remains uncertain, but traditionally it is seen as falling between the reigns of Phraortes and Cyaxares and covering the years 653 to 625 bc. Whether such an interregnum ever actually occurred and, if it did, whether it should not be dated later than this are open questions. What is clear is that by the mid 7th century bc there were a great many Scythians in western Iran, that they—along with the Medes and other groups—posed a serious threat to Assyria, and that their appearance threw previous power alignments quite out of balance.
Herodotus reports how, under Cyaxares of Media (625–585 bc), the Scythians were overthrown when their kings were induced at a supper party to get so drunk that they were then easily slain. It is more likely that about this time either the Scythians withdrew voluntarily from western Iran and went off to plunder elsewhere or they were simply absorbed into a rapidly developing confederation under Median hegemony. Cyaxares is a fully historical figure who appears in the cuneiform sources as Uvakhshatra. Herodotus speaks of how Cyaxares reorganized the Median army into units built around specialized armaments: spearmen, archers, and cavalry. The unified and reorganized Medes were a match for the Assyrians. They attacked one of the important Assyrian border cities, Arrapkha, in 615 bc, surrounded Nineveh in 614 but were unable to capture it, and instead successfully stormed the Assyrian religious capital, Ashur. An alliance between Babylon and the Medes was sealed by the betrothal of Cyaxares’ granddaughter to Babylonian King Nabopolassar’s son, Nebuchadrezzar II (605–562 bc). In 612 the attack on Nineveh was renewed, and the city fell in late August (the Babylonians arrived rather too late to participate fully in the battle). The Babylonians and the Medes together pursued the fleeing Assyrians westward into Syria. Assyrian appeals to Egypt for help came to naught, and the last Assyrian ruler, Ashur-uballiṭ II, disappeared from history in 609.
The problem, of course, was how to divide the spoils among the victors. The cuneiform sources are comparatively silent, but it would seem that the Babylonians fell heir to all of the Assyrian holdings within the Fertile Crescent, while their allies took over all of the highland areas. The Medes gained control over the lands in eastern Anatolia that had once been part of Urartu and eventually became embroiled in war with the Lydians, the dominant political power in western Asia Minor. In 585 bc, probably through the mediation of the Babylonians, peace was established between Media and Lydia, and the Halys (Kızıl) River was fixed as the boundary between the two kingdoms. Thus a new balance of power was established in the Middle East among Medes, Lydians, Babylonians, and, far to the south, Egyptians. At his death Cyaxares controlled vast territories: all of Anatolia to the Halys; the whole of western Iran eastward, perhaps as far as the area of modern Tehrān; and all of southwestern Iran, including Fārs. Whether it is appropriate to call these holdings a kingdom is debatable; one suspects that authority over the various peoples, Iranian and non-Iranian, who occupied these territories was exerted in the form of a confederation such as is implied by the ancient Iranian royal title, king of kings.
Astyages followed his father, Cyaxares, on the Median throne (585–550 bc). Comparatively little is known of his reign. All was not well with the alliance with Babylon, and there is some evidence to suggest that Babylonia may have feared Median power. The latter, however, was soon in no position to threaten others, for Astyages was himself under attack. Indeed, Astyages and the Medians were soon overthrown by the rise to power in the Iranian world of Cyrus II (the Great) of Persia. The rise of the Persians under Cyrus II