- period ~1200 BCE-600 CE defined by widespread use of iron tools and weapons
- iron smelting democratized access to metal: more abundant and harder than bronze
- classical civilizations: Greece, Rome, Persia, Maurya, Han China
- rise of alphabets: Phoenician, Greek, Latin, Aramaic
- Axial Age (~800-200 BCE): philosophy emerged independently in Greece, India, China, Persia
- republican and imperial governance, roads, aqueducts, legal codes
- followed the Bronze Age, transitioned into medieval period
- foundation for Renaissance rediscovery of classical knowledge