Jeroboam was a talented man; when Solomon saw that the young man was an accomplished worker, he made him the leader of the work crew from the tribe of Joseph.
When all Israel heard that Jeroboam had returned, they summoned him to the assembly and made him king over all Israel. No one except the tribe of Judah remained loyal to the Davidic dynasty.
Their descendants remained in the land (the Israelites were unable to wipe them out completely). Solomon conscripted them for his work crews, and they continue in that role to this very day.