II Samuel 2:8-10

But Abner the son of Ner, commander of Saul’s army, took Ishbosheth the son of Saul and brought him over to Mahanaim; and he made him king over Gilead, over the Ashurites, over Jezreel, over Ephraim, over Benjamin, and over all Israel. Ishbosheth, Saul’s son, was forty years old when he began to reign over Israel, and he reigned two years. Only the house of Judah followed David.