Genesis 10:5

5 (From these the maritime peoples spread out into their territories by their clans within their nations, each with its own language.)

Read Genesis 10:5 Using Other Translations

By these were the isles of the Gentiles divided in their lands; every one after his tongue, after their families, in their nations.
From these the coastland peoples spread in their lands, each with his own language, by their clans, in their nations.
Their descendants became the seafaring peoples that spread out to various lands, each identified by its own language, clan, and national identity.

What does Genesis 10:5 mean?

John Gill's Exposition of the Bible
Genesis 10:5

By these were the isles of the Gentiles divided in their
lands
That is, by those sons of Japheth before mentioned; and by "isles" are meant, not countries surrounded with water, for the isles in this sense would not have been sufficient for the posterity of Japheth; nor can it be thought they would leave the continent, where there was room enough for them, and go into islands; and besides must have found it difficult to get there, when shipping and navigation were little known: but it is usual with the Hebrews, of whom Moses, the writer of this history, was, to call all places beyond the Mediterranean sea, or whatsoever they went to by sea, or that were upon the sea coasts, islands, as Greece, Italy Moreover, the word sometimes signifies countries, as it does in ( Job 22:30 ) ( Isaiah 20:6 ) and so should be rendered here, as it is by some F25, "the countries of the Gentiles"; so called, because in the times of Moses, and at the writing of this history, those countries were inhabited by Heathens and idolaters, strangers to the true religion: and this division was not made at random, and at the pleasure of a rude company of men, but in an orderly regular manner, with the consent, and by the advice and direction of the principal men of those times; and especially it was directed by the wise providence of the most High, who divided to the nations their inheritance, and set the bounds of the people, ( Deuteronomy 32:8 ) .

everyone after his tongue, after their families, in their nations;
this shows, that what is said concerning the division of countries to the sons of Japheth is by way of anticipation; and that, though thus related, was not done till after the confusion of languages, since the partition was made according to the different languages of men; those that were of the same language went and dwelt together, the several nations of them, and the several families in those nations; by which it appears that this was done by consultation, with great care and wisdom, ranging the people according to their tongues; of which nations were formed, and with them were taken the several families they consisted of.


FOOTNOTES:

F25 (Mywgh yya) "regiones gentium", Junius & Tremellius, Piscator, Patrick.
California - Do Not Sell My Personal Information  California - CCPA Notice