Cyrus The Great
Cyrus, 599-530 BC, founded the Achaemenid Persian empire and ruled it from 549 to 530 BC. His father was Cambyses I, a prince in Persis, modern Fars province. (The name Cyrus may have meant simply "son" in a local dialect.) His mother, according to Herodotus, was the daughter of Astyages, king of the Medes, who ruled the Persians. Cyrus revolted against his overlord and defeated him, after which the Achaemenid empire was founded. Cyrus first conquered the Iranians who opposed him and then marched against CROESUS, king of Lydia (in present-day Turkey). Cyrus defeated him and captured his capital, Sardis. After consolidating his rule over Ionian Greek cities on the coast of the Aegean Sea, he turned to Babylonia.

The conquest of the great and ancient city of Babylon in 539 BC made Cyrus the ruler of a vast domain from the Mediterranean Sea to the borders of India. Cyrus is famous in the Old Testament for freeing the Jewish captives in Babylonia and sending them back to their home. Cyrus then marched to central Asia, where he was killed in a battle with nomads. He was succeeded by his eldest son, Cambyses II.

The Greek author Xenophon wrote a fanciful biography of Cyrus which depicted him as an ideal ruler. Many legends grew up around the figure of Cyrus, and he came to be considered the father of the Iranian monarchy. The celebration of the 2,500th anniversary of the founding of the monarchy by Iran in 1971 indicates the important place in history held by Cyrus the Great.

Cambyses II
Cambyses II, who succeeded his father, Cyrus The Great, as king of Persia in 529 BC, extended his empire by conquering Egypt in 525. He is said to have murdered his brother Bardiya, and the Greek historian Herodotus claimed that he was insane. After the conquest of Egypt, a pretender claiming to be Bardiya seized the throne, and Cambyses either committed suicide or died accidentally in 522 while returning to Persia.

Darius I
Darius I, an Achaemenid king who ruled from 522 to 486 BC, is considered the restorer of the Persian Empire. Born c.550, he became king after killing the priestly usurper Gaumata, who claimed to be Bardiya (known as Smerdis to the Greeks), younger brother of Cambyses II . Darius's father was Hystaspes, an Achaemenid prince of a collateral line. (Some scholars think that Darius killed the real Bardiya after the death of Cambyses and invented the story that Bardiya had been killed earlier by his brother.) Darius had to fight many rebels against his authority early in his reign and left a record of his struggles in a relief and a trilingual inscription of major linguistic importance on a rock at Behistun.

Darius reorganized the Achaemenid empire into provinces called satrapies. Many other reforms are attributed to him, although he may have been the organizer rather than the originator of the famous postal system on the royal roads, the striking of gold coins called darics, and the Achaemenid bureaucracy. He is said to have ordered the creation of a cuneiform script for the Old Persian language, and he started the building of a complex of palaces and buildings at Perspolis.

Darius invaded the Balkans and southern Russia but was forced to retreat from the latter. Continuing the Persian Wars with the Greeks, he sent an army against Athens, but it was defeated in the Battle of Marathon in 490 BC. He named his son Xerzes I as his successor.

Darius III
Darius III, c.381-330 BC, called Codomannus by the Greeks, was the last Achamenid king of Persia, who ruled from 336-330 BC. His father was Arsames, nephew of Artzxerxes II. Darius did not ascend the throne until he was 45, after the princes in the direct line of the family had been assassinated. His first task was the reconquest (334) of Egypt, which had revolted from Persian rule. Darius was defeated by Alexander The Great at the Battle of Issus (333), where his family was taken captive by the conqueror, then at Gaugamela (331), and he spent the rest of his life fleeing from Alexander. He was assassinated by order of Bessus, the satrap of Bactria, in 330 BC.

Ardashir
Ardashir, d. c.241, was king (AD 224-40) of Persia and founder of the powerful Sassanian dynasty. He is called the son of Papak, a minor prince of Fars province, although some sources maintain that he was the son of an unknown Sasan. Ardashir served as a governor of Firuzabad, where he made his capital, building several great palaces and carving rock reliefs. He revolted against his Parthian overlord, the Arsacid king Artabanus V, whom he defeated and killed in 224. He fought several battles with the Romans and made (c.240) his son SHAPUR I coruler, after which he abdicated. During his reign he reestablished Zoroastrianism as the state religion.

Shapur I
Shapur I, d. AD 272, second Sassanian king of Persia (241-72), son and successor of Ardashir I , attacked Rome's eastern provinces, encouraged the establishment of the Manichaean religion, and promoted the growth of Zoroastrianism. He invaded (256) Anatolia, Armenia, and Syria, and in response the Roman emperor VALERIAN undertook a disastrous campaign against the Persians. Shapur captured (260) Valerian, who died in captivity. Exploiting his Roman prisoners' ability as civil engineers, Shapur used them to build an irrigation dam.

Shapur II
Shapur II, AD 309-79, ninth Sassanian king of Persia (r. 309-79), greatly enhanced the power of the Persian empire. He was the posthumous son and successor of Hormuz II. At first his reign was dominated by the nobility and clergy, but when Shapur came of age, he resolved to regain lost Persian territory to the east and west and to assert his own authority. He subdued central Asian tribes--the Kushans in present-day Afghanistan--and annexed their kingdom. From the Romans he took Amida (Diyarbakir) in 359 and won Armenia shortly before his death. Shapur also sent expeditions far into Arabia against the tribes there and built walls and forts in Mesopotamia to defend against their forays.

Persecution of Christians by Shapur began about 339, after the Roman emperor Constantine I converted to Christianity, and lasted until Shapur's death. Under Shapur, Zoroastrianism became firmly established as the state religion, and society was organized into a caste system. Although the reigns of his immediate successors Ardashir II (379-83) and Shapur III (383-88) were weak and brief, Shapur's reign brought to theSassanian Empire a stability that enabled it to endure until the Arab conquest of the 7th century.

Khosru I
Khosru I, d. 579, called Chosroes in the West, succeeded his father, Kavad, as ruler of Persia in 531. A Sassanian, he is known in Eastern sources as Anushirvan (of immortal soul) because of his fame. For the Arabs his name, rendered as Kisra, became the generic name for all the Sassanian kings.

Khosru reformed the taxation of the Sassanian empire, as well as its military and social structure. He successfully fought the Byzantine Empire, briefly occupying Antioch in 540, and in the East he crushed the nomadic Hephthalites and established Sassanian hegemony over present-day Afghanistan. His troops conquered areas as far away as Yemen and in the Caucasus. A patron of learning, Khosru invited Greek philosophers to his court after their academy was closed in Athens in 529. During his long reign many works were translated from Greek and Sanskrit into Persian. Khosru also built many structures.