How did the Persians consolidate their power and control and influence the subjects of their extensive empire?

The Assyrians rose to power from a base in the Tigris and Euphrates River Valleys of Mesopotamia, which had seen many earlier empires. They were defeated by a coalition that included a Mesopotamian power — Babylon — but also a people with a base of power in a part of the world that had not been the site of earlier urbanized states: Persia (modern-day Iran), a stark land of towering mountains and flaming deserts, with a broad central plateau in the heart of the country (see Map 2.1). The Persians created an even larger empire than the Assyrians did, and one that stretched far to the east. Though as conquerors they willingly used force to accomplish their ends, they also used diplomacy to consolidate their power and generally allowed the peoples that they conquered to practice their existing customs and religions. Thus the Persian Empire was one of political unity and cultural diversity.