Thutmose III (thŭtˈmōz, tŭtˈ–) [key] or Thothmes III thŏthˈmēz, tōtˈmĕs, d. 1436 B.C., king of ancient Egypt, of the XVIII dynasty; the successor of Thutmose II. After the death of Thutmose II, his wife Hatshepsut became regent for Thutmose III and relegated him to an inferior position for 22 years while she ruled Egypt. At her death (1468 B.C.), he emerged as the sole ruler of Egypt and as a great conqueror. Almost immediately he advanced into Syria, where an Asian alliance against Egypt waited to oppose him. He was victor at Megiddo and consolidated all Syria, except Phoenicia, in his empire. In successive campaigns he reduced every ruler N of the Euphrates to the status of autonomous tributary and eventually conquered even powerful Kadesh and Mitanni, a kingdom E of the Euphrates River. His empire (the zenith of the New Empire), extending from the Third Cataract to the Euphrates, was used to enrich Egypt with wealth and manpower. He built temples up and down the Nile and founded the wealth of the priesthood of Amon, to which he belonged. Thutmose died after having made his son Amenhotep II coregent, and was buried in the Valley of the Kings at Thebes. His mummy is now at Cairo.