Medieval Demographics re-visited & Greyhawk Demographics Finally Resolved

 We've all read S. John Ross' seminal Medieval Demographics Made Easy [MDME],  I presume. I for one adore S. John Ross and have spent long hours on his excellent gaming blog. 

Trouble, his piece not as usable as it presents itself to be. At least not for the kind of fantasy setting that seeks to emulate a world with some measure of wilderness to explore. 

Ross' baseline seems to be pre-Black Death 14h century Europe. But I don't consider this to be a good era to use, since it reflects a time where the remnant frontiers of Europe were basically non-existent and internal development in terms of arable land and infrastructure fully exploited.

I would rather look to the 11th century, which strikes a good middle ground between being solidly in the high Middle Ages, but not yet having maximized its population, arable cultivation and development potential. There were still frontiers, tribal lands and unexploited and unexplored lands to find, alongside well developed lands. In short, this period mirrors most closely the kind of land development D&D tends to take as its baseline.

This also gives us a nice platform to further exploration of this: The Domesday book, written in 1086, 20 years after the Norman Conquest of England.

The Domesday book in its 900+ pages of glory

Based on the Domesday Book, there was in 1086 an estimated 1.2m-2m population in England. Spread across 50,000 square miles. That gives 1086 England a population density of 24-40 per square mile.

Ross writes in MDME "The British Isles [in the 14th century] were the least populous, with a little more than 40 people per square mile, most of them clustered in the southern half of the isles."

These numbers are fairly accurate for 14th century British Isles, although it would have been a fair bit lower in the 11th century. His interpretation of those numbers however, are well off. Ross describes a population density of 30/sq.mi this way:

"...realms with gloomy weather, inhospitable terrain, or perhaps a slave-driving Mad King"

But that does not at all describe 11th century England. The very existence of the Domesday Book shows it to have been "rich and effectively administered" and "extensively exploited." And furthermore that "there may have been almost as much land under plough by 1086 as at the start of the First World War."

And the British Isles were far from the "least populous" of 14th century Europe.

The Iberian Peninsula throughout the middle ages had a population density somewhere between 25 and 40 people per square mile (and closer to 25 in the 14th century). These were well developed lands. Denmark had a population density around 30. Kievan Rus had an estimated density throughout the high Middle ages between 9 and 16 per square mile. Sweden around 3(!) and Norway 2(!!!).

France having a population density of 90/sq.mi before the black plague is the anomaly in these assessments. It would not hit similar density again until the modern age. But Ross takes this as his baseline, comparing it to Germany [wrong] and Italy and then contrasting it to the low numbers of the British Isles, even though most of medieval Europe had nowhere near that kind of density in any era.  

Only Italy, Belgium and parts of France could sustain that kind of density in the middle ages and only then during peak development pre-plague times. It's an outlier, not a baseline.

I propose rather that 25-40 people per square mile is closer to the right kind of baseline for a fairly well developed medieval realm. 

And that in itself does not tell you much about how urbanised it is. High density does not neccessarily lead to urbanization. Never really happened in Denmark and Switzerland, despite a solid and stable population density. On the other hand, Kievan Rus, despite being much less densely populated, trended far more towards urbanization. As did Iberia. France did not, whilst the Holy Roman Empire did.

MDME's calculations for cities and towns, though a bit on the lower side, does however match fairly well 11th century England. It had 2 cities (London, Winchester) and some 20 major towns. And since MDME's system is not based on density, but rather a trickle effect based on size of its largest city, this means that this system is actually somewhat well de-coupled and quite usable, despite the distorted baselines for population density. Less so for France, which was very concentrated around Paris in its urbanization compared to Italy or the HRE.

This cover is everything Greyhawk to me.

Once we have this in context, let's try and apply this to a thorny subject: The Howling Emptiness of the Greyhawk Setting. 

Yes Veluna at 5/sq. mi. is quite empty, but not by the orders of magnitude Kutalik imagines compared to "even the wildest places of Europe" (he clearly sources MDME's numbers and interpretation of those numbers).

Multiply by 5 though and you have saner numbers perhaps for a decently settled medieval realm.

The Folio discusses these numbers, saying 20% of the total population constitute "males fit to bear arms". In the boxed set, we are told that the numbers given for humanoids and demi-humans is only for "fighting males" (which we can extrapolate to being 20% of total population). 

If we simply take the total population numbers listed as as "males fit to bear arms" to match how the demi-human and humanoid numbers are interpreted (in the same way as Wilderlands of High Fantasy population numbers assume), then everything falls into place. 

City numbers we leave as is, and this also resolves the grating disparity between those numbers, such as the city of Dyvers having 42.000 citizens supported by an upland of only 13.000 non-urbanites.

And there you have it: Correct what must have been a simply typo on fit males vs total population from the Savant Sage, and that is all that is needed for the Greyhawk population density to make sense. The mystery of Greyhawk's howling emptiness finally resolved!