Ancient Egypt was a civilization in eastern North Africa concentrated along the middle to lower reaches of the Nile River that reached its greatest extent in the second millennium BC during the New Kingdom. It stretched from southern Syria in the north to as far south as Jebel Barkal, located at the Fourth Cataract of the Nile in modern-day Sudan. The fluid geographic range of ancient Egypt also included, at different times, areas of the southern Levant, the Eastern Desert and the Red Sea coastline, the Sinai Peninsula, and the oases of the Western desert.Ancient Egyptian civilization began around 3150 BC with the political unification of Upper and Lower Egypt under the first pharaoh, and it developed over the next three millennia. Its history is divided into a series of golden ages, known as Kingdoms, that are separated by periods of relative instability known as Intermediate Periods. After the end of the last golden age, known as the New Kingdom, the civilization of ancient Egypt entered a period of slow, steady decline, during which Egypt was conquered by a succession of foreign adversaries. The power of the pharaohs officially ended in 31 BC when the early Roman Empire conquered Egypt and made it a province.The civilization of ancient Egypt was based on balanced control of natural and human resources under the leadership of the pharaoh, religious leaders, and court administrators. It was notable for many innovations: controlled irrigation of the fertile Nile Valley, mineral exploitation of the valley and surrounding desert regions, the early development of literature and an independent writing system, the organization of collective construction and agricultural projects, trade with surrounding regions in east and central Africa and the eastern Mediterranean, and finally, military ventures that defeated foreign enemies and asserted Egyptian dominance throughout the region. Motivating and organizing these activities was a bureaucracy of elite scribes, religious leaders, and administrators under the control of the divine pharaoh who ensured the cooperation and unity of the Egyptian people by means of an elaborate system of religious beliefs.