(1) The name of the vassal king of Ellasar, under Chedorlaomer, king of Elam, and Amraphel, king of Shinar (Babylonia), who took part in the expedition against Sodom, Gomorrah and other states (Ge 14:1,9). Assyriologists generally, and probably rightly, identify Arioch with Eri-Aku (which see), king of Larsa, Ellasar being for Al-Larsa (now Sinqara in central Babylonia).
Texts Referring to the Reign of Arioch:
For an account of the expedition see AMRAPHEL, and for the Babylonian texts bearing upon the reign, see ERI-AKU. In Ge 14:1,9, where the names of the allied kings who marched against the Cities of the Plain are given, that of Arioch follows his more immediate suzerain, Amraphel, and not Chedorlaomer, who, however, appears to have been the real overlord (verse 4), which agrees with the indications of the Bah records. No details of the expedition are available from Babylonian sources. Besides Larsa, Eri-Aku's inscriptions inform us that Ur (Muqayyar, Mugheir) was in the principality of which Larsa was the capital.
(2) The Arioch of Da 2:14,25 was captain of the bodyguard of King Nebuchadnezzar. Nothing else is known about him except that it was he who was commanded to slay the "wise men" who failed to repeat to the king his dream and its interpretation; and who communicated to his royal master that Daniel had undertaken the task.
T. G. Pinches