Cambyses II (Καμβύσης, Kambysēs). The eldest son and successor of Cyrus as emperor of the Persian Empire; reigned 530–522 bc.

The mother of Cambyses was Cassandane, a Persian princess. Cambyses had one brother, Bardiya (or Smerdis), whom he may have put to death secretly after he became king. For two or more years, Cambyses was king of Babylon while his father was emperor.

After coming to the throne, Cambyses organized an expedition for the conquest of Egypt, which succeeded in 525 bc. Afterward, Cyrene and Barca (the modern Tripoli) submitted to his rule. Cambyses then attempted to conquer Carthage, but was compelled to give up; his Phoenician allies refused to join in an attack on a country they had colonized. Cambyses’ campaign against Ethiopia was only somewhat better. After some initial successes, he was forced to return to Egypt, where he put down a revolt, executed the Egyptian king, and destroyed many temples.

In 522 bc, Cambyses heard of a revolt in Persepolis, the Persian capital. According to the Behistun Inscription, a man named Gaumata the Magian claimed to be Cambyses’ brother, Bardiya, and set himself up as king of Persia. Cambyses started toward Persia to attack the usurper, but he died on the way. His general and cousin, Darius Hystaspes, soon put down the false Bardiya and ruled instead.