A Commentary, Critical, Practical, and Explanatory on the Old and New Testaments, by Robert Jamieson, A.R. Fausset and David Brown  at sacred-texts.com
gen 10:1GENEALOGIES. (Gen. 10:1-32)
sons of Noah--The historian has not arranged this catalogue according to seniority of birth; for the account begins with the descendants of Japheth, and the line of Ham is given before that of Shem though he is expressly said to be the youngest or younger son of Noah; and Shem was the elder brother of Japheth (Gen 10:21), the true rendering of that passage.
generations, &c.--the narrative of the settlement of nations existing in the time of Moses, perhaps only the principal ones; for though the list comprises the sons of Shem, Ham, and Japheth, all their descendants are not enumerated. Those descendants, with one or two exceptions, are described by names indicative of tribes and nations and ending in the Hebrew im, or the English "-ite."
gen 10:5the isles of the Gentiles--a phrase by which the Hebrews described all countries which were accessible by sea (Isa 11:11; Isa 20:6; Jer 25:22). Such in relation to them were the countries of Europe, the peninsula of Lesser Asia, and the region lying on the east of the Euxine. Accordingly, it was in these quarters the early descendants of Japheth had their settlements.
gen 10:6sons of Ham--emigrated southward, and their settlements were: Cush in Arabia, Canaan in the country known by his name, and Mizraim in Egypt, Upper and Lower. It is generally thought that his father accompanied him and personally superintended the formation of the settlement, whence Egypt was called "the land of Ham" [Psa 105:23, Psa 105:27; Psa 106:22].
gen 10:8Nimrod--mentioned as eclipsing all his family in renown. He early distinguished himself by his daring and successful prowess in hunting wild beasts. By those useful services he earned a title to public gratitude; and, having established a permanent ascendancy over the people, he founded the first kingdom in the world [Gen 10:10].
gen 10:10the beginning of his kingdom--This kingdom, of course, though then considered great, would be comparatively limited in extent, and the towns but small forts.
gen 10:11Out of that land went forth Asshur--or, as the Margin has it, "He [Nimrod] at the head of his army went forth into Assyria," that is, he pushed his conquests into that country.
and builded Nineveh--opposite the town of Mosul, on the Tigris, and the other towns near it. This raid into Assyria was an invasion of the territories of Shem, and hence the name "Nimrod," signifying "rebel," is supposed to have been conferred on him from his daring revolt against the divine distribution.
gen 10:21Unto Shem--The historian introduces him with marked distinction as "the father of Eber," the ancestor of the Hebrews.
gen 10:23Aram--In the general division of the earth, the countries of Armenia, Mesopotamia, and Syria, fell to his descendants.
gen 10:24Arphaxad--The settlement of his posterity was in the extensive valley of Shinar, on the Tigris, towards the southern extremity of Mesopotamia, including the country of Eden and the region on the east side of the river.
gen 10:25Peleg; for in his days was the earth divided--After the flood (Gen 11:10-16) the descendants of Noah settled at pleasure and enjoyed the produce of the undivided soil. But according to divine instruction, made probably through Eber, who seems to have been distinguished for piety or a prophetic character, the earth was divided and his son's name, "Peleg," was given in memory of that event (see Deu 32:8; Act 17:26).
gen 10:32These are the families of the sons of Noah, after their generations, in their nations, &c.--This division was made in the most orderly manner; and the inspired historian evidently intimates that the sons of Noah were ranged according to their nations, and every nation ranked by its families, so that every nation had its assigned territory, and in every nation the tribes, and in every tribe the families, were located by themselves.