How did the city of Uruk grow during the late 4th millennium BCE?

During the late 4th millennium BCE, the city of Uruk experienced a period of significant urbanization characterized by a shift in settlement patterns. Archaeological surveys indicate that the number of small settlements in southern Mesopotamia decreased as the population increasingly concentrated in larger urban centers like Uruk.1

This growth was marked by several key developments:

• Architectural Expansion: Uruk saw an "almost explosive" increase in the size of its buildings. Structures from Uruk Levels VI to IV included massive rectangular buildings, some measuring 275 by 175 feet, which served as temples or assembly halls.1
• Economic Specialization: The city became a center for specialized crafts, including sculpture, seal engraving, and the production of textiles, pottery, and metalwork.12
• State Administration: The emergence of a centralized administration is evidenced by the mass production of standardized vessels known as beveled-rim bowls. These were likely used to issue food rations to a portion of the population, establishing a system where the state maintained workers in exchange for their labor.12
• Invention of Writing: This period saw the birth of the first writing system in the Middle East, which originated as a practical tool for administrative accounting.12