1 Chronicles 5:1–8 (ESV)

1 The sons of Reuben the firstborn of Israel (for he was the firstborn, but because he defiled his father’s couch, his birthright was given to the sons of Joseph the son of Israel, so that he could not be enrolled as the oldest son;

The genealogical section first traces the sons of Reuben for one generation (1 Chronicles 5:1–3). It then mentions the descendants of Joel up to the Assyrian exile (1 Chronicles 5:1–3). Finally, it lists a number of Reubenite chiefs (1 Chronicles 5:7–8). Only the immediate sons of Reuben appear elsewhere in Scripture (see Genesis 46:9; Exodus 6:14; Numbers 26:5–6). Beerah, a descendant of Joel (1 Chronicles 5:6) seems to mark the end of the Reubenite line when they were exiled by Tiglathpileser III (Tiglathpileser here and in 2 Chronicles 28:20) during his campaign into Galilee and the Transjordan in 733–732 BC. This took place during the reign of Pekah (2 Kings 15:29). The whole area of Israelite Transjordan became the Assyrian province of Gal’azu, that is, Gilead or the land beyond the Jordan (Isaiah 9:1).1 Many Reubenites were deported into exile, and this humiliating fact explained why Reuben did not appear important to the Chronicler’s readers.2