(Ἀρβάκης).
1. The founder of the Median empire, according to the account of Ctesias (ap. Diod. 2.24, &c., 32). He is said to have taken Nineveh in conjunction with Belesis, the Babylonian, and to have destroyed the old Assyrian empire under the reign of Sardanapalus, B. C. 876. Ctesias assigns 28 years to the reign of Arbaces, B. C. 876-848, and makes his dynasty consist of eight kings. This account differs from that of Herodotus, who makes Deioces the first king of Media, and assigns only four kings to his dynasty. [DEIOCES.] Ctesias' account of the overthrow of the Assyrian empire by Arbaces is followed by Velleius Paterculus (1.6), Justin (1.3), and Strabo. (xvi. p. 737.)