The original population area of the Median people was western Iran and named after them as "Media".

At the end of the second millennium BCE the Median tribes arrived 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 ninth century until the beginning of the seventh century BCE.

The southern border of Media, in this period, is named as the Elamite region of Simaški in present day Lorestan.

From the west and northwest it is bounded by the Zagros mountains and from the east by Dašt-e Kavir.

The region of Media is known to the Assyrians and described by them thus: "extended along the Great Khorasan Road from just east of Harhar to Alwand, and probably beyond.

It was limited on the north by Mannaea, on the south by Ellipi.

The location of Harhar is suggested to be "the central or eastern" Mahidasht in Kermanshah province.

After ensuring the allegiance of Babylonia, Esarhaddon campaigns in around 678 against the Medes under Khshathrita (Phraortes).

Later, Assyrian hosts reach the border of the "salt-desert" near the mountain Bikni, that is, near Teheran.

A number of fortresses secure the Zagros: Bit-Parnakki, Bit-kari and Harhar (Kar-Sharrukin).