Answer: Akhenaten or Amenhotep IV
Explanation: Amenhotep IV, as he was known for the first five years after coming to power, after which he changed his name to Akhenaten. This Pharaoh was from the 18th Egyptian dynasty and was best known for rejecting the well-known Egyptian polytheism and introducing service and belief in one god Aten. Hence his name after five years of rule is changed to Akhenaten, meaning "Effective for Aten". At first, Aten was equated with a kind of supreme deity, dedicated to the sun, and from there, by scholars, this religion was considered quasi-monotheistic. Later, only the name Aten was thrown out of use, giving it universal significance, the omnipresent, omnipotent God.