The six features of an empire, exactly as the chapter sets them out on page 88, with the emperor exerting central authority over the empire's tributary territories and kings:
| # | Feature | What it involves |
|---|---|---|
| 01 | Army | Maintains an army to keep tributary states under control, expand the empire, or protect it from outside aggression |
| 02 | Administration | Designs and maintains an administration, with officials to manage the territories, collect taxes, maintain law and order |
| 03 | Laws and currency | Makes laws, issues currencies, weights and measures, regulates trade |
| 04 | Resources | Controls and regulates access to resources — mines, forest and agricultural produce, manpower |
| 05 | Culture and learning | Encourages art, literature, religions, schools of thought, centres of learning |
| 06 | Communication | Maintains communication networks — roads, river and sea navigation — and other infrastructure for administration, trade and people's welfare |
How an empire differs from a kingdom:
| Kingdom | Empire | |
|---|---|---|
| Size | One territory, usually of one people | Many territories, often taking two months on horseback to cross |
| Structure | A king ruling his own subjects directly | An emperor ruling over other kings, who become tributaries |
| Ruler's title | rāja | samrāj, adhirāja, rājādhirāja — ‘king of kings’ |
| Income | Taxes from his own people | Taxes plus tribute — gold, grain, livestock, elephants — from tributary kings |
| People | Usually one main language and set of customs | Many languages, customs and cultures under one authority |
| How it is built | Usually inherited | Usually built by war, alliances and submission of neighbours |
| Stability | Comparatively stable and compact | Fragile — far-off territories are the first to break away |