Moab was the son of the Lot’s eldest daughter, the progenitor of the Moabites. Zoar was the cradle of the race of Lot. From this centre the brother tribes spread themselves. The Moabites first inhabited the rich highlands which crown the eastern side of the chasm of the Dead Sea, extending as far north as the mountain of Gilead, from which country they expelled the Emims, the original inhabitants, but they themselves were afterward driven southward by the warlike Amorites, who had crossed the Jordan, and were confined to the country south of the river Arnon, which formed their northern boundary. (Numbers 21:13; Judges 11:18) The territory occupied by Moab at the period of its greatest extent, before the invasion of the Amorites, divided itself naturally into three distinct and independent portions:– (1) The enclosed corner or canton south of the Arnon was the “field of Moab.” (Ruth 1:1-2, 6) etc. (2) The more open rolling country north of the Arnon, opposite Jericho, and up to the hills of Gilead, was the “land of Moab.” (Judges 11:15; Deuteronomy 32:49) etc. (3) The sunk district in the tropical depths of the Jordan valley. (Numbers 22:1) etc. The Israelites, in entering the promised land, did not pass through the Moabites, (Judges 11:18) but conquered the Amorites, who occupied the country from which the Moabites had been so lately expelled. After the conquest of Canaan the relations of Moab with Israel were of a mixed character, sometimes warlike and sometimes peaceable. With the tribe of Benjamin they had at least one severe struggle, in union with their kindred the Ammonites. (Judges 3:12-30) The story of Ruth, on the other hand, testifies to the existence of a friendly intercourse between Moab and Bethlehem, one of the towns of Judah. By his descent from Ruth, David may be said to have had Moabite blood in his veins. He committed his parents to the protection of the king of Moab, when hard pressed by Saul. (1 Samuel 22:3-4) But here all friendly relations stop forever. The next time the name is mentioned is in the account of David’s war, who made the Moabites tributary. (2 Samuel 8:2; 1 Chronicles 18:2) At the disruption of the kingdom Moab seems to have fallen to the northern realm. At the death of Ahab the Moabites refused to pay tribute and asserted their independence, making war upon the kingdom of Judah. (2 Chronicles 22:1) … As a natural consequence of the late events, Israel, Judah and Edom united in an attack on Moab, resulting in the complete overthrow of the Moabites. Falling back into their own country, they were followed and their cities and farms destroyed. Finally, shut up within the walls of his own capital, the king, Mesha, in the sight of the thousands who covered the sides of that vast amphitheater, killed and burnt his child as a propitiatory sacrifice to the cruel gods of his country. Isaiah, chs. (Isaiah 15-16, 25:10-12) predicts the utter annihilation of the Moabites; and they are frequently denounced by the subsequent prophets. For the religion of the Moabites see Chemosh; Molech ; Peor . See also Tristram’s “Land of Moab.” Present condition.–(Noldeke says that the extinction of the Moabites was about A.D. 200, at the time when the Yemen tribes Galib and Gassara entered the eastern districts of the Jordan. Since A.D. 536 the last trace of the name Moab, which lingered in the town of Kir-moab, has given place to Kerak, its modern name. Over the whole region are scattered many ruins of ancient cities; and while the country is almost bare of larger vegetation, it is still a rich pasture-ground, with occasional fields of grain. The land thus gives evidence of its former wealth and power.–ED.)
Smith's Bible Names Dictionary (1866).