The Persian Empire is the name used to refer to a number of historic dynasties that have ruled the country of Persia (Iran). Persia's earliest known kingdom was the proto-Elamite Empire, followed by the Medes; but it is the Achaemenid Empire that emerged under Cyrus the Great that is usually the earliest to be called "Persian.
The first record of the Persians comes from an Assyrian inscription from c. 844 BC that calls them the Parsu (Parsuash, Parsumash) and mentions them in the region of Lake Urmia alongside another group, the Madai (Medes). For the next two centuries, the Persians and Medes were at times tributary to the Assyrians. The region of Parsuash was annexed by Sargon of Assyria around 719 BC. Eventually the Medes came to rule an independent Media Empire, and the Persians were subject to them.
Achaemenid Persia (648 BC-330 BC) was the first state of the Persians. The first king of the Achaemenid Persia was Cyrus the Great and the last one was Darius III. Cyrus the Great was the founder of the Archaemenian dynasty and the Persian Empire. Cyrus' military victories eventually put him in possession of the largest empire in the world at that time. No doubt he was a remarkably humane ruler for his time.
Cyrus the Great founded the empire as a multi-state empire, governed by four capital states; Pasargadae, Babylon, Susa and Ecbatana. Each capital represented a different fact of Persian territorial power. Ecbatana’s significance did not end with the Achaemenid dynasty. Susa was linked with political authorities and cultural influences from both if its regional contexts.
The Achaemenids allowed a certain amount of regional autonomy in the form of the satrapy system. A satrapy was an administrative unit, usually organized on a geographical basis. The satrapies were linked by a 2,500-kilometer highway; the most impressive stretch being the Royal Road from Susa to Sardis, built by...