Akhenaton
... Therefore, he changed his name to Akhenaton, meaning “he who is devoted to Aton. ... Akhenaton ordered the elimination of all traces of the polytheistic religion of his ancestors. ... From his new capital, Akhenaton attacked the cults of other deities in Egypt, especially those of the state god Amon-Re. ... One of the main reasons that Akhenaton decided to make Egypt a monotheistic country and only serve the solar disk, Aton, was because he was afraid of the priests, who were beginning to assume a great deal of the king’s power. Therefore, when Akhenaton made Egypt monotheistic, the priests lost almost all of their power because their temples and religions were destroyed.