How did the peoples of Mesopotamia form states and develop new technologies and institutions?

States first developed in Mesopotamia, where sustained agriculture reliant on irrigation from the Euphrates and Tigris Rivers resulted in larger populations, a division of labor, and the growth of cities. Priests and rulers developed ways to control and organize these complex societies, including armies, taxation systems, and written records. Conquerors from the north unified Mesopotamian city-states into larger empires and spread Mesopotamian culture over a large area.