Analysis of information sources in references of the Wikipedia article "Iran–Iraq relations" in English language version.
The cultural give and take influenced many things, some of which are the cuneiform writing and the building of ziggurats which the later Assyrians and the Achaemenid (Hakhamaneshi) Persians inherited. The Assyrians influenced the cultures of Media and Urartu, and the influence of Elam lived on among the Medes and Persians. The various Iranian speaking peoples who had been migrating into what is now the Caucasus, Iran, Afghanistan and Central Asia were heavily influenced by the aboriginal Elamites and the Semitic Babylonians and Assyrians. This difference can be most noticed when one compares other Iranian speaking peoples who lived in Eurasia like the Scythians and Sarmatians whose culture was very different with that of Iranian tribes who settled in the Iranian Plateau. So from that far back, Iran (the geographic location) has been multi-ethnic.
The cultural give and take influenced many things, some of which are the cuneiform writing and the building of ziggurats which the later Assyrians and the Achaemenid (Hakhamaneshi) Persians inherited. The Assyrians influenced the cultures of Media and Urartu, and the influence of Elam lived on among the Medes and Persians. The various Iranian speaking peoples who had been migrating into what is now the Caucasus, Iran, Afghanistan and Central Asia were heavily influenced by the aboriginal Elamites and the Semitic Babylonians and Assyrians. This difference can be most noticed when one compares other Iranian speaking peoples who lived in Eurasia like the Scythians and Sarmatians whose culture was very different with that of Iranian tribes who settled in the Iranian Plateau. So from that far back, Iran (the geographic location) has been multi-ethnic.