Josiah, son of King Amon, and mother Jedidah, became King of Judah at age 8, and reigned 31 years (639-609 BC). The Bible passage at 2 Kings 22:2 says that the character of Josiah's reign was good, and that he followed in the steps of his ancestor, King David, and was obedient to the Lord.
His reign was the last surge of political independence and religious revival before the disintegration of the Kingdom of Judah, which ended with the destruction of Jerusalem in 586 BC. When Josiah was 20 years old, he began to clean up Judah and Jerusalem, destroying the heathen altars and the shameful idols on the hills, according to 2 Chronicles 34:3.
He did the same thing in the cities of Manasseh, Ephraim, Simeon, and Naphtali. Later on, he set up a collection system for gifts for the Temple, and paid carpenters and masons to repair the Temple, from the damage and neglect by the earlier Kings of Judah.
A scroll was found in the Temple by Hilkiah the High Priest. The scroll, containing the Laws of God, was read to King Josiah. When Josiah found out that the reason for the Lord's great anger on Judah and Israel was that the ancestors had not obeyed the laws written in the scriptures, he ripped his clothing in despair (2 Chronicles 34:21).
Josiah then gathered the elders and all the people to the Temple, read the scroll to them, and required everyone in Jerusalem and Benjamin to make a pledge to the Lord, to follow His Commandments. So, Josiah removed all of the idols from the areas occupied by Jews, and required all of them to worship God (2 Chronicles 34:33).
Josiah held a great Passover celebration that was not seen in Jerusalem since the days of Samuel the prophet. Later, King Neco of Egypt led his army against the Assyrians, and warned King Josiah not to interfere while his army passed through Judah (2 Chronicles 35:21). But Josiah refused to turn back, and led his army into battle at the valley of Megiddo. The enemy archers struck King Josiah with their arrows and fatally wounded him. He died in Jerusalem, and was buried there.
All of Judah mourned for him, including Jeremiah the prophet. Josiah's son, Jehoahaz, was selected as the new king. The story of Josiah is found in 2 Kings, chapters 22 and 23, and 2 Chronicles, chapters 34 and 35. The name Josiah means "May Yah give."
Next person in the Bible: Jotham, or Joatham, King of Judah