Ish-bosheth, originally named Eshbaal, was the youngest of the four sons of King Saul.
He was about forty years old when his father and three brothers including Jonathan fell at the battle of Gilboa. Through the influence of Abner, Saul's cousin, he was acknowledged as successor to the throne of Saul, and ruled over all Israel, except the tribe of Judah, which was ruled by David.
Ish-Bosheth son of Saul was forty years old when he became king over Israel, and he reigned two years. The house of Judah, however, followed David. (2 Samuel 2:10)
After a troubled and uncertain reign he was murdered by Recab and Baanah, two of his own men who were leaders of raiding bands.
Now Recab and Baanah, the sons of Rimmon the Beerothite, set out for the house of Ish-Bosheth, and they arrived there in the heat of the day while he was taking his noonday rest. They went into the inner part of the house as if to get some wheat, and they stabbed him in the stomach. Then Recab and his brother Baanah slipped away.
(2 Samuel 4:5-6)
The cut off his head and presented it to David. If they were expecting a reward, they were disappointed.
David ordered them to be executed.
Ish-Bosheth's head was buried in Abner's tomb at Hebron.