Complex sentence: The pinnacle of this religious hierarchy was the Pharaoh, who was both king and living god, and the administration of the Egyptian kingdom was thus inextricably bound up with, and largely controlled by, the power and influence of the priests and scribes.
Split into simpler sentences: The pinnacle of the religious hierarchy was the Pharaoh, both king and living god. Administration of the Egyptian kingdom was thus inextricably bound up with and largely controlled by the power and influence of the priests and scribes.