Ezek 38:2; "Son of man, set your face toward Gog of the land of Magog, the prince of Rosh, Meshech and Tubal, and prophesy against him
Rev 20:8; and will come out to deceive the nations which are in the four corners of the earth, Gog and Magog, to gather them together for the war; the number of them is like the sand of the seashore.
It seems Noah had three sons, one of them was Japheth.
Gen 5:32; Noah was five hundred years old, and Noah became the father of Shem, Ham, and Japheth.
Gen 6:10; Noah became the father of three sons: Shem, Ham, and Japheth.
Gen 7:13; On the very same day Noah and Shem and Ham and Japheth, the sons of Noah, and Noah's wife and the three wives of his sons with them, entered the ark,
Gen 9:18; Now the sons of Noah who came out of the ark were Shem and Ham and Japheth; and Ham was the father of Canaan.
Japheth had some sons also. One of them was Magog.
Gen 10:2; The sons of Japheth were Gomer and Magog and Madai and Javan and Tubal and Meshech and Tiras.
1Chron 1:5; The sons of Japheth were Gomer, Magog, Madai, Javan, Tubal, Meshech and Tiras.
Ezek 38:2; "Son of man, set your face toward Gog of the land of Magog, the prince of Rosh, Meshech and Tubal, and prophesy against him
Ezek 39:6; "And I will send fire upon Magog and those who inhabit the coastlands in safety; and they will know that I am the LORD.
Jacob and Leah had six sons, One of them was Rueben ( the first born )
1Chron 5:1; Now the sons of Reuben the firstborn of Israel (for he was the firstborn, but because he defiled his father's bed, his birthright was given to the sons of Joseph the son of Israel; so that he is not enrolled in the genealogy according to the birthright.
1Chron 5:2; Though Judah prevailed over his brothers, and from him came the leader, yet the birthright belonged to Joseph),
1Chron 5:3; the sons of Reuben the firstborn of Israel were Hanoch and Pallu, Hezron and Carmi.
1Chron 5:4; The sons of Joel were Shemaiah his son, Gog his son, Shimei his son,
A great grandson of Rueben was Gog. Ezekiel 38 ad 39 talk about Gog and Magog, it seems these lands were named after the people above.
Ezek 38:2; "Son of man, set your face toward Gog of the land of Magog, the prince of Rosh, Meshech and Tubal, and prophesy against him
Ezek 38:3; and say, 'Thus says the Lord GOD, "Behold, I am against you, O Gog, prince of Rosh, Meshech and Tubal.
Ezek 38:14; "Therefore prophesy, son of man, and say to Gog, 'Thus says the Lord GOD, "On that day when My people Israel are living securely, will you not know it?
Ezek 38:16; and you will come up against My people Israel like a cloud to cover the land. It shall come about in the last days that I will bring you against My land, so that the nations may know Me when I am sanctified through you before their eyes, O Gog."
Ezek 38:18; "It will come about on that day, when Gog comes against the land of Israel," declares the Lord GOD, "that My fury will mount up in My anger.
Ezek 39:1; "And you, son of man, prophesy against Gog and say, 'Thus says the Lord GOD, "Behold, I am against you, O Gog, prince of Rosh, Meshech and Tubal;
Ezek 39:11; "On that day I will give Gog a burial ground there in Israel, the valley of those who pass by east of the sea, and it will block off those who would pass by. So they will bury Gog there with all his horde, and they will call it the valley of Hamon-gog.
Here is a Wikipedia article, lacking in a lot of research, (for example it doesn't mention Rueben ) but some of it is correct.
en.wikipedia.org