1 Kings 12:3-4, 20

Rehoboam assembled Jeroboam and all the people. They said to Rehoboam, “Your father made life hard for us—worked our fingers to the bone. Give us a break; lighten up on us and we’ll willingly serve you.”

When the word was out that Jeroboam was back and available, the assembled people invited him and inaugurated him king over all Israel. The only tribe left to the Davidic dynasty was Judah.