sentences:  By this time the Iranian tribes were the majority in what later become the territory of the Median Kingdom and also the west of Media proper.A study of textual sources from the region shows that in the Neo-Assyrian period, the regions of Media, and further to the west and the northwest, had a population with Iranian speaking people as the majority.This period of migration coincided with a power vacuum in the Near East with the Middle Assyrian Empire (1365–1020 BC), which had dominated northwestern Iran and eastern Anatolia and the Caucasus, going into a comparative decline.