2013-12-17

Fantasy Settlements - part 2: Distribution

How often will you find settlements when travelling, either in civilised lands, or the wilderness?

Or, more to the point in fantasy gaming, if I randomly teleport the player characters to the middle of a country, how far are they from the nearest town?

Population density
How often you find settlements will depend on how densely populated the area is.

According to the 2007 Demographic Year Book of the United Nations, there were 49 persons per square km in the surface area of the world. Among the continents, Asia - with a density of 126 persons per square km - was the most densely populated continent, followed by Europe (32), Africa (32), Latin America (28), Northern America (16) and Oceania (4). [Source]

We can use these figures to give us some bench marks for the population density of the fantasy lands we're inventing.
Is our fantasy land crowded, like India? Or sparsely settled, like Australia?

Of course, these figures are from recent times - you might be planning a setting more like medieval Europe, or feudal Japan. We can use historical data to tweak our number fairly easily. For example, here's the Wikipedia entry for historical population - from which we see in the 14th Century, the global population of earth was about 300 million - about 5% of today's population - so for a simple formula, you could divide those figures above by 20...

Except that as we can see from these maps showing population through the ages, we've tended to cluster round some prime habitable area for most of known history. If we're going to assume that a populated area is going to be attractive to live in, then we shouldn't just arithmetically cut the density by 95%. Let's call it half instead, and add a "Wilderness" category, where practically no-one lives.

For a bench mark, I'll set the following density levels:
  • Very high density population: more than 200 per square mile
  • High density: 150 - 200 per square mile
  • Medium density: 75 - 149 per square mile
  • Low density: 30 - 74 per square mile
  • Sparse density: up to 30 per square mile
  • Wilderness: no random population
(I'm mixing my units in this entry, sorry, but population per square km is about one third of the population per square mile - and fantasy games prefer miles. So I've multiplied all those sq km figures by 3.)

Clumps of people

Where is that population, though? Populations are rarely distributed at random. People tend to settle in clumps - that's the technical term, honestly.
We're not just a blanket of people spread out over our respective countries, one per football pitch-sized bit of land. We gather together in settlements.

Urbanisation
As I mentioned before, the d20 fantasy rules seem to steer us to a relatively urbanised population.

In modern times, about 50% of the world's population live in urban areas. In the early stages of industrialisation, 10% of the population lived in towns and cities.
Before industrialisation, however, between 1 and 2% of the population lived in town and cities - the slower transport links of this era meant that 50 to 90 farmers were needed to support just one city-dweller. [sources]

For a typical fantasy setting, a 1% level of urbanisation would be appropriate - travel is by foot or horse, so getting fresh food into urban centres requires a close network of rural population: plenty of villages, hamlets and farmland.

Of course, in some high fantasy settings, magic can take the place of industrialisation, so that the early industrial or even modern distribution might be appropriate. Consider the level of magic, and the ability to rapidly travel. Food production might even be magically achieved. It might even be possible to exceed our real-world modern level of urbanisation.

I'm going to stick with a typical, pre-industrial feel for the fantasy setting. I tweaked the settlement categories so they would shake out to give a more rural population:


  • Metropolis (25 000 +)
  • City (5 001 - 25 000)
  • Large town (2001 - 5000)
  • Small town (501 - 2000)
  • Large village (201 - 500)
  • Small village (61 - 200)
  • Hamlet (21 - 60)
  • Thorp (up to 20)


I've crunched through the maths to find the percentage of the population that lives in each type of settlement, for an arbitrarily large population (large enough to fill all the categories).

  • Metropolis 0.5%
  • City 1%
  • Large town 2.5%
  • Small town 4%
  • Large village 5%
  • Small village 12%
  • Hamlet 25%
  • Thorp 50%
(Notice that over 90% of the population live in rural settlements - most live in communities of just a couple of dozen people... but we still have scope for some huge cities and metropolises.)

Now, from those percentages, for the benchmark densities above in an arbitrarily large area, I worked out how many settlements of each category there would be - from which I worked out how many miles there would be between each settlement...

Settlement distribution by density category

  • Very high density
  • Metropolis - up to 200 miles
  • City - up to 100 miles
  • Large town - 30 miles 
  • Small town - 15 miles
  • Large village - 7 miles
  • Small village - 3 miles
  • Hamlet - 1 mile
  • Thorp - 1/2 mile
  • High density
  • Metropolis - 250 miles
  • City - 125 miles
  • Large town - 33 miles 
  • Small town - 15 miles
  • Large village - 7 miles
  • Small village - 3 miles
  • Hamlet - 1 mile
  • Thorp - 1/2 mile
  • Medium density
  • Metropolis - 300 miles
  • City - 150 miles
  • Large town - 50 miles 
  • Small town - 25 miles
  • Large village - 10 miles
  • Small village - 5 miles
  • Hamlet - 1 1/2 miles
  • Thorp - 1/2 mile
  • Low density
  • Metropolis - 450 miles
  • City - 250 miles
  • Large town - 75 miles 
  • Small town - 30 miles
  • Large village - 15 miles
  • Small village - 5 miles
  • Hamlet - 2 miles
  • Thorp - 1 mile
  • Sparse density
  • Metropolis - 750 miles
  • City - 350 miles
  • Large town - 100 miles 
  • Small town - 50 miles
  • Large village - 25 miles
  • Small village - 10 miles
  • Hamlet - 4 miles
  • Thorp - 2 miles

Random settlement finding

The thorp is the most frequent settlement type, so the distances between those are smallest. But this is also the minimum distance to any settlement. If you randomly appear anywhere in a sparsely populated region (let's ignore true wilderness for the moment), then you are no more than 2 miles from some kind of settlement.
What kind of settlement? Usually, that'd be a thorp - a clump of families, some little ranch and its cowpokes, a remote chapel with its attendant monks, or a country house and its family and staff. But it could be a metropolis, a city, town or village.

We've got a set of percentages of settlement types, and that turns quite neatly into a table. First we check how far away the nearest settlement is, then we roll to see what type of settlement it is.

Once we've got that nearest settlement figured out, the other types of settlement are randomly placed around about. The nearest city will be 350 miles away, the nearest large town, 100 miles, and so on.



Miles to next




d%

very high density
high density
medium density
low density
sparse density
1-50
Thorp
0.5
0.5
0.5
1
2
51-75
Hamlet
1
1
1.5
2
4
76-88
Small village
3
3
5
5
10
89-93
Large village
7
7
10
15
25
94-97
Small town
15
15
25
30
50
98-99
Large town
30
33
50
75
100
00
roll 1d4





1d4

very high density
high density
medium density
low density
sparse density
1-3
City
100
125
150
250
350
4
Metropolis
200
250
300
450
750

Caveats and tweaks

If you're rolling randomly for an utterly new region, this system will work nicely enough - but take a look at 2.5, next, where I discuss location selection by desirability: people tend to build settlements where there's some resource to make the settlement worthwhile.

But if you're designing a setting, you'll probably have some ideas about where the capital city is, and where some other key major places are. (These are almost certainly placed in the most desirable spots - be sure to check out 2.5 next time!)

Remove metropolises and cities from the table - they only count for 1.5% of the total, anyway. You'll be left with town, villages and smaller settlements - just the sort of size of place for you to quickly put together some notes and wing it.