https://www.btstories.com/jehoshaphats-victory/

Jehoshaphat was 35 years old when he became king of Judah. He ruled for 25 years. He set up an educational system, established justice in the land, and reformed the legal system.

Things were going well in Judah, until suddenly the nations of Moab, Ammon, and Edom decided to unite together and fight against Jehoshaphat. A massive army moved from the east side of the Dead Sea to En-gedi, on the west side.