On the death of Cyrus
the Great in 530 BC, his son Cambyses came to the throne
. While travelling from Syria
to crush opposition there in 522 BC, he was accidentally killed. Darius
, an army officer who had been spearbearer to Cambyses and came from a branch of the Achaemenid family, continued the march to Persia
and succeeded in crushing the rebellion
As is the case with Cyrus, the details of Darius's reign that have passed to posterity are based on his version of events. For example, the account of his defeat of the rebels is contained in a great inscription he had carved at Bisitun, high on a cliff face overlooking the Great Khorasan Road. The inscription not only relates how Darius crushed the revolt and came to power, but also proclaims his right to rule through his paternal ancestors. In reality, it seems that he gained the throne by leading the party of nobles who opposed the rebellion and by controlling much of the army. The revolt was widespread, and the restoration of peace took more than a year to achieve.
In the early years of his reign, Darius mounted an expedition to India, where he annexed the Sind and possibly the Punjab. Less successful was his campaign against the Scythians to the north of the Black Sea. In spite of this failure, it was under Darius that the Persian Empire reached its greatest extent, embracing lands that stretched from the Indus River in the east as far as Libya in the west.
Darius was a brilliant administrator and divided the empire into provinces, or satrapies. There were twenty of these, according to Herodotus, and each had its own governor, or satrap, usually a Persian noble or member of the royal family. A separate official, in charge of the army, was responsible for collecting the annual tribute, which was paid not only in gold or silver, but also in kind. The reliefs of the tribute bearers from Persepolis depict a wide range of products, including ivory from Ethiopia, incense from Arabia and even camels from Bactria.
Darius moved his capital from Pasargadae to Susa and made it the main administrative center, although the old capital continued to be used, probably for ceremonial purposes. The climate of Susa was warmer, and in the summer the court moved to the cooler heights of Ecbatana, the old Median capital. Darius's construction work at Susa was extensive and included an "apadana" (a columned audience hall) and a new palace. Both here and at Persepolis, craftsmen from all over the empire worked at the palaces he built. In the one adjoining the apadana at Susa, Babylonian craftsmen made panels of molded polychrome glazed tiles to decorate the walls. One showed a frieze of royal guards, the Ten Thousand Immortals, honored by the king in gratitude for their support.