Tribe of Reuben

According to the Hebrew Bible, the Tribe of Reuben (Hebrew: שֵׁבֶט רְאוּבֵן, Modern Shevet Re'uven, Tiberian Šḗḇeṭ Rəʼûḇēn) was one of the twelve tribes of Israel.

From after the conquest of the land under Joshua until the formation of the first Kingdom of Israel in c. 1050 BC, the Tribe of Reuben was a part of a loose confederation of Israelite tribes. No central government existed, and in times of crisis the people were led by ad hoc leaders known as Judges. (see the Book of Judges) With the growth of the threat from Philistine incursions, the Israelite tribes decided to form a strong centralised monarchy to meet the challenge, and the Tribe of Reuben joined the new kingdom with Saul as the first king. After the death of Saul, all the tribes other than Judah remained loyal to the House of Saul, but after the death of Ish-bosheth, Saul's son and successor to the throne of Israel, the Tribe of Reuben joined the other northern Israelite tribes in making David, who was then the king of Judah, king of a re-united Kingdom of Israel. According to the Book of Chronicles, Adina and thirty Reubenites aided David as members of his mighty warriors in conquering the City of David. However, on the accession of Rehoboam, David's grandson, in c. 930 BC the northern tribes split from the House of David to reform a Kingdom of Israel as the Northern Kingdom. Reuben was a member of the kingdom until the kingdom was conquered by Assyria in c. 723 BC and the population deported.

...
Wikipedia