WHO ARE THE EDOMITES?

Map of the Territory of the Edomites

The Edomites were the descendants of Esau (Gen 25:25; 36:1) and lived in strong mountain fortresses. They became prosperous through agriculture, cattle, and the tribute they levied on passing caravans.

After the Babylonian captivity the Edomites were driven north by the Nabataeans to the areas around southern Judah and Hebron, which was called Idumea in the Greco-Roman period. The whole area was conquered by John Hyrcanus. Antipater and his son Herod the great were Idumeans. In rabbinical literature Edom was a pseudonym for Rome.

Genesis 36:43 - Duke Magdiel, duke Iram: these [be] the dukes of Edom, according to their habitations in the land of their possession: he [is] Esau the father of the Edomites.

The Edomites in the Bible Encyclopedia - ISBE

Edom
2. Character and Features:
The land thus indicated varies greatly in character and features. South of the Dead Sea in the bottom of the valley we have first the stretch of salt marsh land called es-Sebkha; then, beyond the line of white cliffs that crosses the valley diagonally from Northwest to Southeast, a broad depression strewn with stones and sandhills, the debris of an old sea bottom, rises gradually, and 60 miles to the South reaches a height of about 700 ft. above the level of the Red Sea, 2,000 ft. above that of the Dead Sea. From this point it sinks until it reaches the shore of the Gulf of `Aqaba, 45 miles farther South. The whole depression is known today as Wady el-`Arabah (compare Hebrew ha-`arabhah, Dt 2:8 the Revised Version (British and American), etc.). On either side the mountains rise steeply from the valley, their edges carved into many fantastic shapes by the deep wadys that break down from the interior (see ARABAH). The northern part of the plateau on the West forms the spacious grazing ground of the `Azdzimeh Arabs. The mountains rise to a height of from about 1,500 ft. to a little over 2,000 ft. This district was traversed by the ancient caravan road to South Palestine; and along the eastern side traces of the former civilization are still to be seen. The desert region to the South is higher, reaching to as much as 2,600 ft. The mountain range East of the `Arabah is generally higher in the South than in the North. Jebel Harun beside Petra, is 4,780 ft. above sea-level; while East of `Aqaba, Jebel el-Chisma may be as much as 5,900 ft. in height. Limestone, porphyry and Nubian sandstone are the prevailing formation; but volcanic rocks are also found. The range consists mainly of rough rocky heights with many almost inaccessible peaks separated by deep gorges. But there are also breadths of fertile land where wheat, grapes, figs, pomegranates and olives are grown to advantage. The northern district is known today by the name el-Jebal, corresponding to the ancient Gebal. Seir is the name applied to the eastern range in Gen 36:8; Dt 2:1,5; 2 Ch 20:23. It is also called Edom, and the Mount of Esau (Ob 1:8 f). Seir, however, is used for the western highlands in Dt 33:2. This seems to be its meaning also in Jdg 5:4, where it appears as the equivalent of "the field of Edom." With this same phrase, however, in Gen 32:3 it may more fitly apply to the eastern range.

5. Idumaea and the Idumeans:
West of the `Arabah the country they occupied came to be known by the Greek name Idumaea, and the people as Idumeans. Hebron, their chief city, was taken by Judas Maccabeus in 165 BC (1 Macc 4:29,61; 5:65). In 126 BC the country was subdued by John Hyrcanus, who compelled the people to become Jews and to submit to circumcision. Antipater, governor of Idumaea, was made procurator of Judea, Samaria and Galilee by Julius Caesar. He paved the way to the throne for his son Herod the Great. With the fall of Judah under the Romans, Idumaea disappears from history.
The names of several Edomite deities are known: Hadad, Qaus, Koze, and, possibly, Edom; but of the religion of Edom we are without information. The language differed little from Hebrew. Full Article

The Edomites from Smith's Bible Dictionary

Edom, Idumaea or Idumea (red). The name Edom was given to Esau, the first-born son of Isaac and twin brother of Jacob, when he sold his birthright to the latter for a meal of lentil pottage. The country which the Lord subsequently gave to Esau was hence called "the country of Edom," Ge 32:3 and his descendants were called Edomites. Edom was called Mount Seir and Idumea also. Edom was wholly a mountainous country. It embraced the narrow mountainous tract (about 100 miles long by 20 broad) extending along the eastern side of the Arabah from the northern end of the Gulf of Elath to near the southern end of the Dead Sea. The ancient capital of Edom was Bozrah (Buseireh). Sela (Petra) appears to have been the principal stronghold in the days of Amaziah (B.C. 838). 2Ki 14:7 Elath and Ezion-geber were the seaports. 2Sa 8:14; 1Ki 9:26 History. --Esau's bitter hatred to his brother Jacob for fraudulently obtaining his blessing appears to have been inherited by his latest posterity. The Edomites peremptorily refused to permit the Israelites to pass through their land. Nu 20:18-21 For a period of 400 years we hear no more of the Edomites. They were then attacked and defeated by Saul, 1Sa 14:47 and some forty years later by David. 2Sa 8:13,14 In the reign of Jehoshaphat (B.c. 914) the Edomites attempted to invade Israel, but failed. 2Ch 20:22 They joined Nebuchadnezzar when that king besieged Jerusalem. For their cruelty at this time they were fearfully denounced by the later prophets. Isa 34:5-8; 63:1-4; Jer 49:17 After this they settled in southern Palestine, and for more than four centuries continued to prosper. But during the warlike rule of the Maccabees they were again completely subdued, and even forced to conform to Jewish laws and rites, and submit to the government of Jewish prefects. The Edomites were now incorporated with the Jewish nation. They were idolaters. 2Ch 25:14,15,20 Their habits were singular. The Horites, their predecessors in Mount Seir, were, as their name implies, troglodytes, or dwellers in caves; and the Edomites seem to have adopted their dwellings as well as their country. Everywhere we meet with caves and grottos hewn in the soft sandstone strata. Full Article

The Bible Mentions "Edomites" in many places:

2 Chronicles 25:19 - Thou sayest, Lo, thou hast smitten the Edomites; and thine heart lifteth thee up to boast: abide now at home; why shouldest thou meddle to [thine] hurt, that thou shouldest fall, [even] thou, and Judah with thee?

1 Kings 11:1 - But king Solomon loved many strange women, together with the daughter of Pharaoh, women of the Moabites, Ammonites, Edomites, Zidonians, [and] Hittites;

2 Kings 8:21 - So Joram went over to Zair, and all the chariots with him: and he rose by night, and smote the Edomites which compassed him about, and the captains of the chariots: and the people fled into their tents.

Genesis 36:43 - Duke Magdiel, duke Iram: these [be] the dukes of Edom, according to their habitations in the land of their possession: he [is] Esau the father of the Edomites.

2 Chronicles 25:14 - Now it came to pass, after that Amaziah was come from the slaughter of the Edomites, that he brought the gods of the children of Seir, and set them up [to be] his gods, and bowed down himself before them, and burned incense unto them.

2 Chronicles 21:10 - So the Edomites revolted from under the hand of Judah unto this day. The same time [also] did Libnah revolt from under his hand; because he had forsaken the LORD God of his fathers.

2 Chronicles 21:9 - Then Jehoram went forth with his princes, and all his chariots with him: and he rose up by night, and smote the Edomites which compassed him in, and the captains of the chariots.

1 Kings 11:17 - That Hadad fled, he and certain Edomites of his father's servants with him, to go into Egypt; Hadad [being] yet a little child.

1 Chronicles 18:13 - And he put garrisons in Edom; and all the Edomites became David's servants. Thus the LORD preserved David whithersoever he went.

1 Chronicles 18:12 - Moreover Abishai the son of Zeruiah slew of the Edomites in the valley of salt eighteen thousand.

2 Chronicles 21:8 - In his days the Edomites revolted from under the dominion of Judah, and made themselves a king.

Genesis 36:9 - And these [are] the generations of Esau the father of the Edomites in mount Seir:

2 Chronicles 28:17 - For again the Edomites had come and smitten Judah, and carried away captives.

Mark 3:8 - And from Jerusalem, and from Idumaea, and [from] beyond Jordan; and they about Tyre and Sidon, a great multitude, when they had heard what great things he did, came unto him.

Source: http://www.bible-history.com/maps/edomites.html