Easton's Bible Dictionary
After the Flood the earth was re-peopled by the descendants of Noah, "the sons of Japheth" (Genesis 10:2 ), "the sons of Ham" (6), and "the sons of Shem" (22). It is important to notice that modern ethnological science, reasoning from a careful analysis of facts, has arrived at the conclusion that there is a three-fold division of the human family, corresponding in a remarkable way with the great ethnological chapter of the book of Genesis (10). The three great races thus distinguished are called the Semitic, Aryan, and Turanian (Allophylian). "Setting aside the cases where the ethnic names employed are of doubtful application, it cannot reasonably be questioned that the author [of Genesis 10 ] has in his account of the sons of Japheth classed together the Cymry or Celts (Gomer), the Medes (Madai), and the Ionians or Greeks (Javan), thereby anticipating what has become known in modern times as the 'Indo-European Theory,' or the essential unity of the Aryan (Asiatic) race with the principal races of Europe, indicated by the Celts and the Ionians. Nor can it be doubted that he has thrown together under the one head of 'children of Shem' the Assyrians (Asshur), the Syrians (Aram), the Hebrews (Eber), and the Joktanian Arabs (Joktan), four of the principal races which modern ethnology recognizes under the heading of 'Semitic.' Again, under the heading of 'sons of Ham,' the author has arranged 'Cush', i.e., the Ethiopians; 'Mizraim,' the people of Egypt; 'Sheba and Dedan,' or certain of the Southern Arabs; and 'Nimrod,' or the ancient people of Babylon, four races between which the latest linguistic researches have established a close affinity" (Rawlinson's Hist. Illustrations).
These dictionary topics are from M.G. Easton M.A., D.D., Illustrated Bible Dictionary, Third Edition, published by Thomas Nelson, 1897. Public Domain.
Easton, Matthew George. Entry for 'Japheth'. Easton's Bible Dictionary. https://www.studylight.org/dictionaries/eng/ebd/j/japheth.html. 1897.