Agrarian civilizations, emerging around 3200 BCE, developed independently in regions such as Mesopotamia, Egypt, the Indus Valley, and China, characterized by large populations, surplus food production, and social hierarchies. These states and empires relied heavily on agricultural advancements and formed political, economic, and religious institutions to manage resources and power. While many shared common traits like writing systems and social stratification, differences arose in connectivity, trade, and cultural practices between early civilizations across different continents.