Thursday, April 20, 2017

The Long-Term Impact of Roman Roads

Some economists ran the statistics comparing the distribution of major Roman roads with city populations 1200-1850 and with the amount of light you see across Europe in a satellite image.

They find a strong correlation between Roman roads and population density even today.

Which is interesting, but I am not sure it says much about Roman roads. It does say something rather dramatic about the population structure of western Europe over the past 2,000 years: most of the great Roman cities are still great cities, and within the empire few new places have appeared to rival them.

To test for the impact of Roman roads in particular you would have to somehow identify territories that are very similar except for the presence or absence of a road, and I am not sure how that would be done. Anyway these guys did not do it.


JEL said...

This seems extremely silly to me. Roman cities occupied large arable zones; the roads connected them. The same agricultural conditions attracted people to the same places later, so of course settlement patterns appear to map onto the Roman roads. What interests me (and what needs explaining) is the large modern conurbations where the Romans did _not_ settle heavily: looking at that modern population map, the Low Countries, the coast of Portugal, the UK Midlands, Tyneside, and Glasgow-Edinburgh. The world was warmer than, and some of those areas (like the Scottish lowlands) more fruitful than in modern times. Why didn't the Romans push the locals back and settle them?


John said...

Perhaps what northern Britain and the coast of Portugal have in common is that they are too far from the centers of the Roman world to have developed much, but instead developed when the Americans and the trade route around Africa to India were discovered, turning the Atlantic seaboard into prime territory.

The Netherlands is tougher. Surely the technology used to drain the marshes was within reach of the Romans. But perhaps again the region was not that valuable until new trade routes developed -- to America, to Russia -- and the northern Atlantic fishing industry really got going.