Charles Ellicott Commentary Genesis 10:7

"And the sons of Cush: Seba, and Havilah, and Sabtah, and Raamah, and Sabteca; and the sons of Raamah: Sheba, and Dedan." — Genesis 10:7 (ASV)

Sons of Cush. Cush had five subdivisions, one of which was again divided into two. These are:

1. Seba: This was the name at that time of an Arabian tribe that later migrated into Africa and settled in Meroë. According to Josephus, Meroë still bore this name in his day. They also left their name on the eastern side of the Red Sea, not far north of the Straits of Bab-el-Mandeb.
2. Havilah: Located on the Pison River (Genesis 2:11), Havilah was undoubtedly a region of Arabia, probably situated on the Persian Gulf. Havilah is mentioned again in Genesis 10:29.
3. Sabtah: Probably Hadramaut, in Arabia Felix. (See Note on Genesis 10:26.)
4. Raamah: Located on the Persian Gulf, Raamah was divided into Dedan on the southwest and Sheba in the center, while Havilah lay on the northwest side. Of these, Sheba later rose to fame as the kingdom of the Himyarite Arabs.
5. Sabtechah: Apparently even further south of Dedan, but some place it on the eastern side of the gulf.

Therefore, at the time this table was written, the southern half of Arabia was Cushite. A dark-skinned people is still found there, especially in Yemen and Hadramaut, who are far darker than the light brown Arabians. Migrating from place to place along the seashore, the Cushites' passage into Nubia and Abyssinia was easy.

However, their chief home during this period was in Mesopotamia. Cuneiform inscriptions have now revealed their long struggle there with people of the lineage of Shem.