The God in question would have been the creator god or chief god.
The city-state model of Ur and other Sumerian cities was probably copied to Egypt.
These walled cities in Sumeria were sited on rivers.
They were built around a central temple mound.
The first city in Egypt was Nekhen in Upper Egypt.
It had a central temple and mound.
The chief god of the Sumerian city was Enki, later Enlil.
The 'En' part of which means Sumerian 'god'.
The Sumerians farmed the fertile land between the two rivers known as 'the garden of Eden'.
Ed-En probably means 'earth of god'
The Semite god was called El (later eloha and Allah).
(It is still evident in biblical names such as Michael, Rachel, Daniel, etc)
The Semites clashed and superceded the Sumerians and replaced the En god.
It is not known what happened to the Sumerians.
The clash was later recorded as the Caen and Abel story.
Ca-En was the Sumerian farmer and Ab-El the semetic nomad shepherd.
The god of the central temple of Nekhen would have been Amun or Am-En.
(Later we have At-En adopted by Akhenaten)
The temple was closely associated with Horus the falcon.
The serekhs show the falcon above the temple.
Horus was the symbol of the sun.
The sun was considered a manifestation of the creator god.
The Horus falcon predates the temple at Nekhen.
It may have been a local Egyptian deity that was fused with Amun (Amen).
Later we find Amun fused with the sun god to become Amun-Re.