- Purple: nomadic pastoralists
- Yellow: hunter-gatherers
- Brown: empires
- Green: simple farming societies
- Orange: complex farming societies/chiefdoms
- Blue: state societies
- Dark green: Iranian/Persian, Greek and Hellenized states and empires
- Red: Roman Republic and its dependencies
- White: uninhabited
Author: Briangotts?
I wish we adopted HE already.