I think the Egyptians came up with the idea of one God a little earlier than the Abrahamic religions - Nefertiti and her King the Egyptian Pharaoh Amenhotep IV. some say it was Nefertiti who initiated the new religion. She also had the position as a priest, and she was a devoted worshipper of the god Aten. Amenhotep IV took the name Akhenaten when he and Nefertiti put the sun god Aten at the center of religious worship. Under their reign the traditional gods of Egypt were more or less abandoned at least by the royal family in favor of a single god, the sun disk named Aten.

another early religion was the cult of the ancient Indo-Iranian Sun-god Mithra. The origin of the cult of Mithra dates from the time that the Hindus and Persians still formed one people, for the god Mithra occurs in both the Hindu Vedas and in the Persian Avesta. Followers had an interesting concept of one god in which the first principle or highest God was "Infinite Time".

That is a view certainly beyond an form of idolatry, and comes closer to the buddhist/hindu view of a conscious universe.