Early civilizations were the first complex societies with cities, governments, and organized systems. They appeared around 3000 BCE in different parts of the world. Many developed near rivers for water and farming.

Examples include Mesopotamia between the Tigris and Euphrates rivers, Ancient Egypt along the Nile, the Indus Valley, and early China near the Yellow River. These societies created writing systems, laws, and trade networks.

Archaeologists study ruins, tools, and written records to learn about these civilizations. Their developments influenced later societies and cultures.