CHAPTER 5 Sep. 22 
The Children of Reuben
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; and the genealogy is not to be reckoned after the birthright. 2For Judah prevailed above his brothers, and of him came the prince; but the birthright was Joseph’s): 3the sons of Reuben the firstborn of Israel: Hanoch, Pallu, Hezron and Carmi. 4The sons of Joel: Shemaiah his son, Gog his son, Shimei his son, 5Micah his son, Reaiah his son, Baal his son, 6and Beerah his son, whom Tiglath Pilneser king of Assyria carried away captive: he was prince of the Reubenites. 7His brothers by their families, when the genealogy of their generations was reckoned: the chief, Jeiel, and Zechariah, 8and Bela the son of Azaz, the son of Shema, the son of Joel, who lived in Aroer, even up to Nebo and Baal Meon: 9and eastward he lived even to the entrance of the wilderness from the river Euphrates, because their livestock were multiplied in the land of Gilead. 10In the days of Saul, they made war with the Hagrites, who fell by their hand; and they lived in their tents throughout all the land east of Gilead. 
The Children of Gad
11The sons of Gad lived over against them, in the land of Bashan to Salecah: 12Joel the chief, Shapham the second, Janai and Shaphat, in Bashan. 13Their brothers of their fathers’ houses: Michael, Meshullam, Sheba, Jorai, Jacan, Zia and Eber, seven. 14These were the sons of Abihail, the son of Huri, the son of Jaroah, the son of Gilead, the son of Michael, the son of Jeshishai, the son of Jahdo, the son of Buz; 15Ahi the son of Abdiel, the son of Guni, chief of their fathers’ houses. 16They lived in Gilead in Bashan, and in its towns, and in all the suburbs of Sharon, as far as their borders. 17All these were reckoned by genealogies in the days of Jotham king of Judah, and in the days of Jeroboam king of Israel. 18The sons of Reuben, and the Gadites, and the half-tribe of Manasseh, of valiant men, men able to bear buckler and sword, and to shoot with bow, and skilful in war, were forty-four thousand seven hundred and sixty, that were able to go forth to war. 19They made war with the Hagrites, with Jetur, Naphish and Nodab. 20They were helped against them, and the Hagrites were delivered into their hand, and all who were with them; for they cried to God in the battle, and He was entreated of them, because they put their trust in Him. 21They took away their livestock; of their camels fifty thousand, and of sheep two hundred and fifty thousand, and of donkeys two thousand, and of men one hundred thousand. 22For there fell many slain, because the war was of God. They lived in their place until the captivity. 
The Children of Manasseh
23The children of the half-tribe of Manasseh lived in the land: they increased from Bashan to Baal Hermon, Senir and Mount Hermon. 24These were the heads of their fathers’ houses: even Epher, Ishi, Eliel, Azriel, Jeremiah, Hodaviah and Jahdiel, mighty men of valour, famous men, heads of their fathers’ houses. 25They trespassed against the God of their fathers, and played the prostitute after the gods of the peoples of the land, whom God destroyed before them. 26The God of Israel stirred up the spirit of Pul king of Assyria, and the spirit of Tiglath Pilneser king of Assyria, and he carried them away, even the Reubenites, and the Gadites, and the half-tribe of Manasseh, and brought them to Halah, Habor and Hara, and to the river of Gozan, to this day.

Commentary

5:4 Gog is mentioned in Ez. 38 as leading a latter day invasion of Israel. The background to 'Gog' given here is that he was an apostate Jew who went away from the God of Israel, attracted by the grazing grounds to the north east of Israel, and who eventually ended up living permanently in the land of Israel's enemies, the land of the Hagarenes (sons of Hagar) and Assyria. The Gog of Ez. 38 may well be an apostate Jew (after the pattern of Rabshakeh) who leads an invasion of his ancient homeland. He attacks because he loves cattle (Ez. 38:11,12)- which was a characteristic of the Gog of 1 Chron. 5. 
5:26 God… stirred up the spirit of Pul- God is able to work directly on the mind or spirit of people, even of unbelievers. What we are desperate for is spiritual mindedness, strength of mind / spirit against the flesh; and surely God is willing to give this to us if we ask Him.
To this day- This implies the Chronicles were written whilst Judah were in captivity; the genealogical records therefore had primary relevance to the exiles returning to Judah.