An Egyptian king, the son and successor of Psammetichus (B.C. 610-594), the contemporary of Josiah, king of Judah. For some reason he proclaimed war against the king of Assyria. He led forth a powerful army and marched northward, but was met by the king of Judah at Megiddo, who refused him a passage through his territory. Here a fierce battle was fought and Josiah was slain (2 Chronicles 35:20-24). Possibly, as some suppose, Necho may have brought his army by sea to some port to the north of Dor (Comp. Joshua 11:2; 12:23), a Phoenician town at no great distance from Megiddo. After this battle Necho marched on to Carchemish (q.v.), where he met and conquered the Assyrian army, and thus all the Syrian provinces, including Palestine, came under his dominion.
On his return march he deposed Jehoahaz, who had succeeded his father Josiah, and made Eliakim, Josiah's eldest son, whose name he changed into Jehoiakim, king. Jehoahaz he carried down into Egypt, where he died (2 Kings 23:31; 2 Chronicles 36:1-4). Four years after this conquest Necho again marched to the Euphrates; but here he was met and his army routed by the Chaldeans (B.C. 606) under Nebuchadnezzar, who drove the Egyptians back, and took from them all the territory they had conquered, from the Euphrates unto the "river of Egypt" (Jeremiah 46:2; 2 Kings 24:7, 8). Soon after this Necho died, and was succeeded by his son, Psammetichus II. (see NEBUCHADNEZZAR.)