The writer of the biblical book of Kings rates Josiah as the highest of all the kings of Judah after David. He is known primarily as a religious reformer, but his vision of Judah motivated political changes, foreign-policy changes, and a measure of reunification with the northern kingdom of Israel (Samaria).
He began to reign at the age of eight, when his father Amon was assassinated, and ruled for 31 years. Going back to the time of Hezekiah, Judah had been bullied by Assyria, although the capital had never fallen. His grandfather and father both had made big religious concessions to the Assyrians and to native religious groups.
In contrast to his father and grandfather Josiah showed a pious loyalty to the traditional Judaean faith, perhaps coming under the influence of the temple priests in Jerusalem. By the age of 20 he was willing to go public with his religious agenda.
He made it clear that he wanted to return to the God of his ancestors and cast away the foreign gods and their worship customs. Such customs included things like child sacrifices and fertility rituals.
Perhaps he was bold because it was clear that Assyria was going through a civil war, as the Babylonian Chronicle points out; perhaps he knew that the Assyrian ruler Ashurbanipal was too old to conduct a campaign; or perhaps he was encouraged through his communication with Assyria’s rivals in Egypt and Babylon.
Gradually Josiah became more and more assertive about his religious goals. He made repairs on the temple; he purged the temple precincts of foreign religions and altars; then he broadened his geographical sweep to include attacks on foreign religious sites in Israel (Samaria).
Josiah then discovered a religious law book, often thought to be some form of the biblical book of Deuteronomy with its laws on the temple, orthodox doctrines, and centralized government. Some have speculated that this document was reformulated into some kind of Deuteronomic history, covering the biblical books from Joshua-Kings.
The climax of Josiah’s reforms came with an invitation for all the people of Israel and Judah to join together for a celebration of the Passover. In addition to remembering the rite of Israel’s escape from Egypt, Josiah also led the people in rededicating themselves to observing the covenant of Moses.
Josiah died when a new pharaoh, Neco II (c. 609-594 b.c.e.), marched across the coastal plains to challenge Babylonia and Persia as the emerging powers of Mesopotamia. The Bible says that Josiah opposed Neco, interfering with the divine intention for Egypt to have the right of way.
The picture is murky, for it is not clear why Josiah stood against Neco, nor why the divine plan favored of Egypt’s passage. Josiah, who the Bible hails as the most faithful of kings, was mortally wounded on the battlefield, a casualty of the divine plan.