# How to calculate your kingdom’s population size?

How do I figure out the population numbers in my various kingdoms?

I've seen the population growth tables for the entire world showing how the population grew and died off over time (yes Genghis, I'm talking about you).

But how do I figure out the number of people in my various kingdoms. I can't just say it was a large million people strong population with medieval society and knowledge in an area the size of say, Denmark. (this is just an example).

To work out the number of soldiers I could legitimately field, or the number of large cities, or how much farmland I need etc I need to figure out just how many people are in the country.

Is this one of the times where the answer is however many you want? Or is there a somewhat 'established' calculation of people per area per time period/society level?

Or is the answer the reverse? Figure out how much farmland you have, that can feed the cities and soldiers. Work it out by number of mouths I can feed?

Does anyone have a handy 'farming productivity through the ages' almanac?

• Oh I like this question! Only I fear it will end up in some sort of weird circle reference or sth like that :( – dot_Sp0T Oct 6 '16 at 15:00
• Similar question worldbuilding.stackexchange.com/questions/9582/… that might provide some clues. – Steve Mangiameli Oct 6 '16 at 15:07
• For quick litmus tests, if you know your country is the size of, say, Denmark, you can always look up Denmark population numbers for the relevant technology period. – Azuaron Oct 6 '16 at 17:01
• I think your question is similar to the one I asked here and some of the answers given would be of interest to you. I would also recommend this link This has estimates for the following information from Roman times: birth and death rates, specific city populations, population densities, the percentage of slaves the urban to rural split of the population and much more. One thing to keep in mind – Slarty Nov 12 '17 at 21:56

This is one of those answers that I can't write up the information on and there is a lot to, but there are really great sources of information which means I'm just going to post a link and a few tools based on that info.

To use these most accurately you should know information about your kingdoms which you'd know from world mapping them and such. You also need area of the kingdom. To get this, if you have Photoshop, open the histogram window and select the area inside your kingdom's borders. This will give you the number pixels selected and you should know the 1 px = km^2 or miles^2 number. Just multiply and you got your area.

See, it depends.

The high of the Medieval era lasted from about 1000 CE to about 1400 CE. From this time the entire world's population was roughly 300 million to 440 million, based on the Population Bureau Reference's estimates.

During this time Europe's population approximated at between 50 and 84 million. Unless, of course, you're dealing with the Late Medieval Age, when everyone started dying of plagues. Assuming we're in the prime of the Medieval era, however, those numbers should do fine.

This averages out to a population density of around 13-21 people per square mile.

So from here you just need to find the size of your kingdom for a good starting estimate. Your example was a region the size of Denmark, so let's start with that.

Crunching those numbers, you have a plausible population range of between 215 thousand and 350 thousand for that size and time period.

From here you can distribute your populations and arrange your kingdom accordingly.

Assuming you have various kingdoms in Europe (where the Medieval era was prominent), here's the TL;DR :

Multiply the population density of Europe in the Medieval Ages (13-21 people per square mile) by the size of your kingdom. From there you should increase or decrease that base population accordingly, based on the nature of your kingdom (is it a major trade center or majorly farmland? etc.)

Hope this helps!

• What do you mean with ACE? I've never seen that designation and based on it's usage and similarity I gotta think it's an mistaken use of CE, but I obviously don't know all the designations ^.^ – Durakken Oct 7 '16 at 14:08
• I intended to use CE. Fixed. – A. Forty Oct 7 '16 at 14:10

Taxes could be a way. If every adult male pays a certain amount of taxes every year then all you need is to count your yearly income to find out what the number of fighting men.

• The question is asking how a worldbuilder would estimate a realistic population number for the kingdom they are crafting, not how the fictional characters in a story would arrive at the same number. – type_outcast Oct 7 '16 at 1:53