BBC: Genesis 10:1-5
These are the generations of the sons of Noah, Shem, Ham, and Japheth. Sons were born to them after the flood.
The sons of Japheth: Gomer, Magog, Madai, Javan, Tubal, Meshech, and Tiras. The sons of Gomer: Ashkenaz, Riphath, and Togarmah. The sons of Javan: Elishah, Tarshish, Kittim, and Dodanim. From these the coastland peoples spread in their lands, each with his own language, by their clans, in their nations. – Genesis 10:1-5
The sons of Japheth and their sons are mostly inhabitants of lands beyond the scope of the Old Testament revelation. Though a few peoples will eventually enter into the history of Israel from lands sharing these names, the line of Japheth is truly given “enlarged tents” (Gen 9:27) without being given the special relationship to God that Shem receives (9:26).
From this first set of examples, it can be seen that this genealogy extends up to and through the Tower of Babel (Gen 11:1-9) so that within two generations, the delivered people are in rebellion again against the commandments of God. This narrative of genealogy provides both insights on future peoples as well as the deliverance that would come through Abram (Gen 12) as the “second Noah”.