I originally posted this on the Necromancer Games Judges Guild forum in 2007
This info is taken from Triumphant Grand Tactical and Demographics found in Wilderlands of High Fantasy (old) and the Ready Ref Sheets
1 able bodied men = 4 to 5 people or 1 household.
1 sq mile will feed 320 able bodied men
1 sq mile needs 30 able bodied men to utilize at 100%
1 5 mile hex has 13,856 acres
1 5 mile hex has 21.65 sq miles
1 5 mile hex has 625 .2 mile hexes
1 .2 mile hex has 22.17 acres
1 .2 mile hex has .035 sq miles
1 5 mile hex, with 100% utilization, can feed up to 6928 people.
1 5 mile hex will require 650 able bodied men to utilize at 100%
Note the book give 6400. This looks like a math error unless they are making note you are never going really get 100% utilization. If you want to do this then the max utilization is 80%.
1 .2 mile hex will feed 11.085 able bodied men
1 .2 mile hex will require 1.039 able bodied men
1 historical manor has 1500 acres
(includes a hamlet or village)
1 historical manor will need 70 able bodied men for labor
1 historical manor will feed 750 people.
640 acres to feed 1 able bodied nomad/hunter gatherer.
1 5 mile hex will feed 20 able bodied nomads (I rounded it)
30 .2 mile hexes will feed 1 able bodied nomad.
I use this as a guide to plot how large the settled areas of the map area. As for this being historically accurate it good enough for the games we play. It is generous on the amount of people that can be can supported by cultivation. Also remember that Judges Guild considers for every able bodied man there are 4 to 5 times number of people (children, elderly, invalid, etc).
The big oversight of this system is accounting for pastoral nomads (those who herd animals) which can get more out of a given set of acreage than hunter gatherers.