Answer: The youngest king in the Bible was Josiah who was the grandson of Manasseh, king of Judah, and ascended the throne at age eight after the assassination of his father, Amon, in 641
Step-by-step explanation:
He reigned for 40 years. (2 Kings 12:1, 2 Chronicles 24:1) He was succeeded by his son, Amaziah of Judah