Cyrus's empire still echoes in a plateau once called Persia
Iran—historic Persia—occupies a West Asian plateau between Mesopotamia, the Caspian, and the Gulf. The Medes unified the territory in the seventh century BCE; Cyrus the Great's sixth-century Achaemenid realm set a high-water mark before Alexander's conquest and later Iranian recoveries.
Iran borders Iraq, Turkey, Azerbaijan, Armenia, Turkmenistan, Afghanistan and Pakistan, with the Caspian to the north and the Persian Gulf and Gulf of Oman to the south. Hominins were present about 800,000 years ago, and many Middle Paleolithic sites, some linked to Neanderthals, lie in the Zagros. Susa, later the capital of Elam and of the Achaemenids, was first settled around 4400 BC, and Proto-Elamite writing, older than cuneiform, dates from the early third millennium BC.
The Medes formed the first Iranian state; in 612 BC Cyaxares and Babylon's Nabopolassar destroyed Nineveh, bringing down Assyria. Cyrus the Great then defeated the Medes and conquered Lydia and Babylon, and Darius the Great built at Persepolis and improved the Royal Road from Susa to Sardis. After the Greco-Persian Wars, Alexander defeated Darius III at Granicus, Issus and Gaugamela between 334 and 331 BC.
The Parthian Arsacids, from the Parni tribe, took Babylonia in 142 BC and ruled for about five centuries until Ardashir I killed Artabanus IV in 224 AD and founded the Sasanian Empire, which revived Zoroastrianism. Long wars with Byzantium weakened it, and the Rashidun Caliphate conquered it between 632 and 654. Most Iranians gradually became Muslim, yet Middle Persian stayed the caliphate's language of business for a time, and the Caspian highlands of Daylam and Tabaristan long resisted Arab rule.
The Abbasid revolution of 747–750 drew support from non-Arab converts, and as caliphal power faded in the 9th and 10th centuries independent Iranian dynasties sparked a cultural renaissance. The Safavids made Twelver Shia Islam the state religion in the 16th century, and the 1979 revolution created the Islamic Republic, in which an unelected supreme leader stands above elected bodies.
Source: Iran
