Final answer:
The city-states of Sumer were interconnected through trade networks, shared religious practices, and cultural exchange despite lacking a single ruler.
Step-by-step explanation:
The various city-states of Sumer were interconnected despite lacking a single ruler through trade networks and economic exchange, shared religious practices and beliefs, and cultural exchange and language similarities. Firstly, long-distance trade played a crucial role in connecting the city-states with each other and beyond. Mesopotamian traders sailed as far as modern-day Pakistan and traded with the people of the Indus River valley. Additionally, the city-states shared religious practices and beliefs, as each city had its own patron god or goddess and temple dedicated to them. Finally, there was a cultural exchange and similarities in language, as the Sumerians and Akkadians lived alongside each other and adapted each other's culture over time.