Advice on Population Density

Alex - I’ve been kicking the tires on creating a fantasy version of feudal Japan (for use with ACKS) and the historic population figures lead to high densities. Wikipedia had pretty good rolled up demographic info so I’m taking a top-down approach. I’m trying to solve for the split between city and domain population, and a target density for non-urban areas.


The region of Kinai accounts for 8.63% of the population in periods later than 1600. Rolling the population back from 34mm to 12mm (a number more realistic for 1600ish) Kinai would still have 1,035,600 people (people - not families).

The area is 2,654 square miles, giving a density of 390.2 people/square mile - much denser than Europe.

The big factor to bring down the regional density is to push people into cities. For instance - Izumi is a province in Kinai, 100,800 people, density of 500/square mile. There are 4 major cities (Tarui, Kishiwada, Hamadera, and Sakai). Even getting the provincial density down to the 200 people/square mile would mean putting 60,000 people in the 4 cities - nearly 60% - but that’s a bit higher than supported by the “Desired Urban Demographics column shifts” on page 231.

The simple answer might be to use a 3 column shift adjustment for feudal Japan to allow larger cities, assuming that intensive agriculture supported them. The alternative is to have a much higher ratio of people per square mile and thus more families per 6 mile hex. Any thoughts on either the urban shift or an appropriate target population density?

My hope is you have a lot more experience running the numbers all the way through and would know which decisions affect the balance of revenues and consequently the size of the armies supported, since that’s ultimately why I think the economics are cool. At the end of the day, this is all a background exercise to help me figure out how big are the armies out in the varies provinces, and for applying the demographics of leveled characters.

My sense is a Mesoamerican campaign might have similar issues - high density urban populations because of more efficient or intensive agriculture than Europe.

BTW - unrelated to this question - would you mind sharing any insight how you tackled adapting ACKS to your own OA themed setting? I’m leaning towards just adding a few appropriate proficiencies, but otherwise leaving classes similar to the core book (plus the assassin) - but I am curious if you ended up adapting OA classes or adding new race-classes for your home game.

I had posted some previous questions here: