2 Samuel 2:9-10

9And he made him king over 1Gilead, over the 2Ashurites, over 3Jezreel, over Ephraim, and over Benjamin, even over all Israel.

10Ish-bosheth, Saul’s son, was forty years old when he became king over Israel, and he was king for two years. The house of Judah, however, followed David.