It is now widely believed that Central Asia has been the cradle of all human history and civilization and Iran is no less than a core to this cradle. If we consider "settlement" - with all its peripherals - as a form of at least primary civilized life, we may then easily trace a form of history in Iran which dates back to 5000 BC. But the word Iran (which means Land of the Aryans and did not appear until about 600 AD) refers to the vast country with a sophisticated form of civilization and it is somewhere around 1000 BC when the history of the Persian empire began, with an irruption of Aryan tribes from the north.
  Among these tribes, who migrated from north to south, two were the most  vigorous and powerful and have been remembered by their biblical names as Medes & Persians. The Medes moved west and north-west to Media; their great age came at the beginning of the sixth century, after they had overthrown Assyria, their neighbor. The Persians went south towards the Gulf, establishing themselves in Khuzistan (on the edge of the Tigris valley and in the old kingdom of Elam) and Fars, the Persia of the ancients.
  Oral traditions preserve a story of legendary kings more important for the light it throws on later Persian attitudes to kingship than as history. It was from the Persian dynasty of the Achaemenids that there descended the first king of a united Persia. He was Cyrus, the conqueror of Babylon.  In 549 BC he humbled the last king of the Medes, swallowed Babylon, advanced through Asia Minor to the sea and dropped down to Syria and Palestine. He then crossed the Hindu Kush and set up supremacy over Gandhara.
  This was the largest empire and civilization the world had seen until that time. Its style was different from its predecessors. Savagery and brutality was not celebrated in official art and Cyrus was careful to respect the institutions and ways of his new subjects. The result was a diverse empire, but a powerful one, commanding loyalties of a kind lacking to its predecessors. He was not a ruthless conqueror. There are notable religious symptoms; the protection of Marduk was solicited for Cyrus's assumption of the Babylonian kingship and at Jerusalem he launched the rebuilding of the Temple.
  The name Persia (as an empire deeply rooted in the heart of human's history)  is no doubt linked to the name & legacy of Cyrus The Great. He got the title "King of Kings" and his stone tomb in Pasargad stood up against the 2500 years of turbulent history of Iran. Numerous bloody battles scratched the face of Persia since Cyrus's eternal rest at Pasargad and ruthless invasions occurred one after the other. But soon after each invasion the conquerors found themselves absorbed in the Persian culture. It was this mysterious power of dissolving the mannerism and culture of invaders into Persian culture that gave our nation the ability to survive against all devastating attacks throughout the history