[sabbatic13]

"Sturdy roads, aqueducts, buildings, and military equipment are basically the things you want to have in order to consolidate and maintain power over a large area for a long period of time." The first three are also the things you want to have, well, civilization. You know, clean water, the ability to conduct trade outside of your immediate area, etc. It's about economics, not control.

[JoeAltmaier]

Strangely, policing roads is a major factor in civilization. If you can't get your goods to market in the next town because of road bandits, then the towns are effectively cut off from one another.

There's even an argument (somebody's thesis) that patrolling roads was the single greatest event (invention?) that led to the end of the so-called dark ages and the beginning of the Renaissance.

Let me see if I can remember the chain: Safe roads led to trade, the return of currency as a valuable resource, the need of Lords for gold instead of cattle, oxen and straw which led to the rewriting of traditional peon contracts. Following that, inflation drove the Lords out of the counties to the cities, lifting the yoke of the local despots and freeing the country.