The oldest son of Israel was Reuben. But since he dishonored his father by sleeping with one of his father's concubines, his birthright was given to the sons of his brother Joseph. For this reason, Reuben is not listed in the genealogical records as the firstborn son.
During the reign of Saul, the Reubenites defeated the Hagrites in battle. Then they moved into the Hagrite settlements all along the eastern edge of Gilead.
There were 44,760 capable warriors in the armies of Reuben, Gad, and the half-tribe of Manasseh. They were all skilled in combat and armed with shields, swords, and bows.
Many of the Hagrites were killed in the battle because God was fighting against them. The people of Reuben, Gad, and Manasseh lived in their land until they were taken into exile.
These were the leaders of their clans: Epher, Ishi, Eliel, Azriel, Jeremiah, Hodaviah, and Jahdiel. These men had a great reputation as mighty warriors and leaders of their clans.
So the God of Israel caused King Pul of Assyria (also known as Tiglath-pileser) to invade the land and take away the people of Reuben, Gad, and the half-tribe of Manasseh as captives. The Assyrians exiled them to Halah, Habor, Hara, and the Gozan River, where they remain to this day.