Jamieson, Fausset and Brown on Job 1:17

17. Chaldeans--not merely robbers as the Sabeans; but experienced in war, as is implied by "they set in array three bands" (Ha 1:6-8). Rawlinson distinguishes three periods: 1. When their seat of empire was in the south, towards the confluence of the Tigris and Euphrates. The Chaldean period, from 2300 B.C. to 1500 B.C. In this period was Chedorlaomer (Ge 14:1), the Kudur of Hur or Ur of the Chaldees, in the Assyrian inscriptions, and the conqueror of Syria. 2. From 1500 to 625 B.C., the Assyrian period. 3. From 625 to 538 B.C. (when Cyrus the Persian took Babylon), the Babylonian period. "Chaldees" in Hebrew--Chasaim. They were akin, perhaps, to the Hebrews, as Abraham's sojourn in Ur, and the name "Chesed," a nephew of Abraham, imply. The three bands were probably in order to attack the three separate thousands of Job's camels (Job 1:3).