What is the New Kingdom pharaoh Amenhotep IV (Akhenaten) known for

Answer: Establishing monotheism and abandoning traditional Egyptian polytheism

Explanation: The 18th dynasty Egyptian Pharaoh, Amenhotep IV or else known as Akhenaten, is best known for establishing a type of monotheism and forbidding traditional Egyptian polytheism. Initially it was the supreme deity equated with the sun called Aten, by which Amenhotep himself changed his name to Akhenaten after the fifth year of his reign. Subsequently, that supreme deity, in order to emphasise monotheism, was transformed into a kind of universal deity with the forbidden mention of his name.

Answer: demanding that his people practice a new monotheistic religion