Each area is assigned a number, normally between 2 and 8. This is the number
                 of acres of land that are required to sustain a single person. Good land
                 has a value of 2; average land is 3-4, and rough or barren land may go as
                 high as 8. Higher than that and most people don't bother--or they go to
                 herding.

                 Then, given the average number for a given town, city or country, you can
                 assign a rural:urban ratio, which will proably be between 4:1 and 10:1,
                 depending on how consistantly good (or bad) the land is.

                 Thorin has some tremendously fertile land in Greenlen, and very nice land
                 in both Gar and Rhyn, but otherwise the land is too rough to do much with it.
                 This means that the average number for Greenlen might be 2, while Gar and
                 Rhyn are both 3. The values for the other areas might be closer to 7.

                 This probably sets the overall "land quality" number to about 4-5. So maybe
                 there will be 6 farmers for each city dweller (a random value--no game
                 mechanic exists yet to map these values.) Which means that Thorin's total
                 population is probably around 2.75 million people, given the following: