Jehoshaphat reigned from 872 to 848 BC, including a two-year co-regency with his father, Asa. Asa's last years were marked by conflicts and oppression. Jehoshaphat needed to strengthen his rule in Judah to bring back peace and stability. During Asa's time, Israel was an enemy, but Jehoshaphat soon formed an alliance with Ahab (2 Chronicles 18:1–2).