According to the Chronicle of Nabonidus, Astyages launched an attack on Cyrus, “king of Ansan”. According to the historian Herodotus, it is known that Astyages gave Harpagus command of the Median army to conquer Cyrus. However, Harpagus contacted Cyrus and encouraged his revolt against Media, before finally defecting with some nobles and part of the army. This mutiny is confirmed by the Chronicle of Nabonidus. The chronicle suggests that hostilities lasted at least three years (553-550), and the final battle ended with the capture of Ecbatana. This was described in the paragraph preceding Nabonidus` entry for Year 7, which described Cyrus` victory and his grandfather`s capture. According to historians Herodotus and Ctesias, Cyrus spared Astyages` life and married his daughter Amytis. This marriage pacified several vassals, including the Bactrians, Parthians and Saka.  Herodotus notes that Cyrus also subjugated Sogdia during his campaigns of 546-539 BC. AD and incorporated it into the empire.   In historical artifacts discovered in the ancient ruins of Babylon and Ur, Cyrus identifies himself as king of Iran, where he reigned from 559 BC. A.D. until his death. He was the first ruler whose name was added with the words the Great (Vazraka in Old Persian, Bozorg in New Persian), a title adopted by many others after him, including the later Achaemenid Shah, Darius the Great and Alexander the Great, who overthrew the Achaemenid dynasty two centuries after Cyrus` death.
Cambyses II was the eldest son of Cyrus and his beloved wife Cassandana. After the conquest of Babylon in 539 BC, Cambyses was appointed governor of northern Babylonia. A position he held for nine months before being fired for unknown reasons. He later took part in Cyrus` ill-fated expedition against the Massagetae, but was sent home before his father`s death. As king of Persia, Cambyses soon came into conflict with Egypt, the last great power in the Middle East. Cambyses II first worked to isolate Egypt from its allies in Greece and Caria and to conquer Cyprus, which served as an important Egyptian base. He also worked to remove Sinai`s rapprochement with Egypt. Cambyses II launched his Egyptian invasion in 525 BC. A.D. and, despite fierce resistance, conquered the country after several months. Other campaigns added Cyrene and parts of Libya to the Persian Empire, but an invasion of Ethiopia failed. According to Professor Richard Nelson Frye, Cyrus – whose abilities as conqueror and steward, according to Frye, are attested by the longevity and vitality of the Achaemenid Empire – had an almost mythical role among the Persians “similar to that of Romulus and Remus in Rome or Moses to the Israelites”, with a story that “follows in many details the stories of heroes and conquerors from other parts of the ancient world”.
 Frye writes: “He became the embodiment of the great qualities expected of a ruler in antiquity, and he assumed heroic traits as a tolerant, magnanimous, courageous and daring conqueror. His personality, as seen by the Greeks, influenced them and Alexander the Great, and since the tradition was passed down from the Romans, it can be assumed that it still influences our thinking today.  Towards the end of September 539 BC. J.-C. The armies of Cyrus under the command of Gubaru, the governor of Gutium, attacked Opis on the Tigris and defeated the Babylonians after a small revolt of the citizens. With Opis under their power, the Persians took control of the vast canal system of Babylon. Darius I, nicknamed Darius the Great (550 BC; † 486), king of Persia in 522-486 BC. AD, one of the greatest rulers of the Achaemenid dynasty, known for his administrative genius and for his large construction projects. Darius tried several times to conquer Greece; his fleet was destroyed by a storm in 492, and the Athenians defeated his army at Marathon in 490.
Darius was the son of Hystaspe, the satrap (provincial governor) of Parthia. The most important contemporary sources for its history are its own inscriptions, especially the large trilingual inscription on Bīsitūn (Behistun) Rock in the village. (100 words out of 1236) After Cyrus` death, his eldest son, Cambyses II, succeeded him as king of Persia. His younger son Smerdis died before Cambyses left to enter the Eastern Front.