Battle of Megiddo
The Battle of Megiddo is recorded as having taken place in 609 BC when Pharaoh Necho II of Egypt led his army to Carchemish (northern Syria) to join with his allies, the fading Neo-Assyrian Empire, against the surging Neo-Babylonian Empire. This required passing through territory controlled by the Kingdom of Judah. The Judaean king Josiah refused to let the Egyptians pass. The Judaean forces battled the Egyptians at Megiddo, resulting in Josiah's death and his kingdom becoming a vassal state of Egypt. The battle is recorded in the Hebrew Bible, the Greek 1 Esdras, and the writings of Josephus.
While Necho II gained control of the Kingdom of Judah, the combined Assyrian-Egyptian forces lost to the Babylonians at the Fall of Harran, after which Assyria largely ceased to exist as an independent state.
The Battle of Megiddo in ancient sources
Book of Kings
2 Kings 23:29-30 -- In his days Pharaoh Neco king of Egypt went up to the king of Assyria to the river Euphrates. King Josiah went to meet him; and Pharaoh Neco slew him at Megiddo, when he saw him. And his servants carried him dead in a chariot from Megiddo, and brought him to Jerusalem, and buried him in his own tomb.
Book of Chronicles
2 Chr 35:20–25 -- After all this, when Josiah had set the temple in order, Neco king of Egypt came up to make war at Carchemish on the Euphrates, and Josiah went out to engage him. But Neco sent messengers to him, saying, "What have we to do with each other, O King of Judah? I am not coming against you today but against the house with which I am at war, and God has ordered me to hurry. Stop for your own sake from interfering with God who is with me, so that He will not destroy you." However, Josiah would not turn away from him, but disguised himself in order to make war with him; nor did he listen to the words of Neco from the mouth of God, but came to make war on the plain of Megiddo. The archers shot King Josiah, and the king said to his servants, "Take me away, for I am badly wounded." So his servants took him out of the chariot and carried him in the second chariot which he had, and brought him to Jerusalem where he died and was buried in the tombs of his fathers.
Josephus, Antiquities
Ant X, 5 -- 1. Now Neco, king of Egypt, raised an army, and marched to the river Euphrates, in order to fight with the Medes and Babylonians, who had overthrown the dominion of the Assyrians, 8 for he had a desire to reign over Asia. Now when he was come to the city Mendes, which belonged to the kingdom of Josiah, he brought an army to hinder him from passing through his own country, in his expedition against the Medes. Now Neco sent a herald to Josiah, and told him that he did not make this expedition against him, but was making haste to Euphrates; and desired that he would not provoke him to fight against him, because he obstructed his march to the place whither he had resolved to go. But Josiah did not admit of this advice of Neco, but put himself into a posture to hinder him from his intended march. I suppose it was fate that pushed him on this conduct, that it might take an occasion against him; for as he was setting his army in array, 9 and rode about in his chariot, from one wing of his army to another, one of the Egyptians shot an arrow at him, and put an end to his eagerness of fighting; for being sorely wounded, he command a retreat to be sounded for his army, and returned to Jerusalem, and died of that wound; and was magnificently buried in the sepulcher of his fathers, when he had lived thirty-nine years, and of them had reigned thirty-one.