Cyrus built the largest empire the world had yet seen
Iran’s plateau holds continuous urban life back to the fifth millennium BC. Medes first unified the land in the seventh century BC; by 550 BC Cyrus the Great’s Persians had overturned them and soon ruled from Anatolia toward the Indus—the biggest empire yet assembled.
Paleolithic tools and Neanderthal finds cluster in the Zagros; a Neanderthal radius turned up at Bisitun Cave in 1949. Early farming villages such as Chogha Golan (eleventh millennium BC) and Chogha Bonut (ninth) rose in the hills; Susa may have been founded as early as about 4395 BC. Elam emerged as a state around 4000 BC with Susa as capital; Jiroft in Kerman yielded fourth-millennium chlorite carvings and what excavators call the world’s earliest inscription. By the mid-first millennium BC Medes, Persians, and Parthians peopled the plateau under Assyrian pressure until Median consolidation.
Ashurbanipal sacked Susa in 646 BC, ending Elamite supremacy. Deioces united the Medes; in 612 BC his grandson Cyaxares and Babylon’s Nabopolassar destroyed Nineveh and toppled Assyria. Cyrus then overthrew Median, Lydian, and Neo-Babylonian realms with comparatively conciliatory rule as “King of Kings.” Cambyses II took Egypt; Darius I seized power, made Susa his first capital, began Persepolis, rebuilt a Nile–Red Sea canal, standardized the gold daric and silver shekel, and organized the Royal Road from Susa to Sardis.
Alexander’s Macedonians shattered the Achaemenids in the fourth century BC; Seleucids, then Parthians, then Sasanians kept Iran a great power through centuries of Roman–Persian wars. Seventh-century Muslim conquest folded Sasanian lands into the Rashidun Caliphate and began Islamization, yet Persian identity absorbed and reshaped its conquerors through the Islamic Golden Age. The Safavids reunified the country from 1501 and made Twelver Shiʿa Islam the state faith—the sharpest religious turn since the original conquest—before later Qajar losses to Russia and twentieth-century upheavals remade the state again.
Source: History of Iran
