Thematic Bible: Remained as one people until the reign of rehoboam

When all Israel saw that the king did not listen to them, the people answered the king, saying, "What portion do we have in David? We have no inheritance in the son of Jesse; To your tents, O Israel! Now look after your own house, David!" So Israel departed to their tents. But as for the sons of Israel who lived in the cities of Judah, Rehoboam reigned over them. Then King Rehoboam sent Adoram, who was over the forced labor, and all Israel stoned him to death. And King Rehoboam made haste to mount his chariot to flee to Jerusalem. read more.
So Israel has been in rebellion against the house of David to this day. It came about when all Israel heard that Jeroboam had returned, that they sent and called him to the assembly and made him king over all Israel. None but the tribe of Judah followed the house of David.