What influences population in Illyriad?

Several things in Illyriad are based off of population (when you can start your next city for instance), and my population is definitely growing, but I don't know what influences it. Does population grow with time, excess food, or activity (building, producing, etc)?

Solution 1:

It is directly based on the level of building you have built and that buildings food consumption on a 1:1 basis. However, some buildings increase faster in food consumption than others.

If you run out of food you can only upgrade resource structures (e.g. farms); but can't queue production of items, troops, do research or build non-resource buildings so its worth keeping an eye on your stockpile.

Population/food consumed also is related to your gold income. At 25% tax your income is 4 x your population.

http://forum.illyriad.co.uk/gold-pop-food-consumed_topic176.html