These are the so-called Semites, or Semitic tribes.
Shem
He is placed in and north of the Arabian Peninsula.
Children of Shem: Elam, Asshur, Arphaxad, Lud, Aram
Elam, Asshur, and Aram (Syria) were all Mesopotamian. Lud was purportedly located in northwest Asia Minor, while the location of Arphaxad is unknown.
Children of Aram: Uz, Hul, Gether, Mash
Uz and Hul were apparently in the desert south of Syria, near Canaan, while Mash was north of Elam and Gether’s location is unknown.
Children of Arphaxad
Here was have not a list of Arphaxad’s immediate offspring but instead a genealogical line, as follows: Arphaxad > Salah > Eber > Peleg and Joktan. Salah’s location is unknown, but Eber—after whom the Hebrews were named—and his son Peleg lived in northern Mesopotamia, in southern Turkey, or northern modern Syria. Joktan lived in the Arabian desert.
Children of Joktan
The names of Gen 10:26-29 are, like the line of Cain and many more to follow, listed in detail as “the road not traveled” by the genealogy that would lead to the kingdom of Israel and the Messiah. The names, which I will not bother listing, are all held to be the 13 original and “purest” Arabian tribes. The names can be found around the Arabian peninsula, especially the southern end, and even (in the case of Ophir) possibly in Africa on the other side of the entrance of the Red Sea.
As to his location and those of his descendants, see the table above. His name is the source of the word “Semite.” This implies that not just Hebrews, but all the Arab tribes, as well as Syrians, probably the Babylonian and Assyrian peasantry, and a number of others, were considered Semitic. But among those who were not deemed Semitic included the Canaanites (most importantly), the Egyptians, and Nimrod, the founder of Babylonia if not many of the people. Note that not all the people who were purportedly descended from Shem spoke a language of the Semitic language family; some spoke an Indo-European language. That the connections are close enough is interesting. As to Eber, it was he after whom the Hebrews were named.
Simply because his descendants are listed in the next chapter, where Abram (later, Abraham) is found to be the great-great-great-great-grandson of Eber.
The name “Eber” means “the other side” as in “the other side of the flood,” so the other side of the Euphrates. This was the land of Haran, from which Isaac and Jacob got wives. If the homeland of Eber was in northern Syria, as it is widely thought, then indeed it might be identified with the land of Haran, where Terah took his family, including Abram, after they left “Ur of the Chaldeans.” So, whatever the reason for the move, they were coming back to their ancestral homeland. Abraham sought a wife for Isaac from the same place, and Rebekah told Jacob to find a wife there as well.
“Peleg” means “division”; the verb in “was divided” is פָלַג or palag, glossed “split, divide.” This is thought to refer to the scattering of ethnic groups and languages at the time of the Tower of Babel.