Montijo max pop (EC): 21'900
Ozrat max pop (FEI): 7'900
I don't know which revisions we're at, but Tom is right: there are a couple rural regions with more population than some small cities.
Don't know what revision they're at, but on BT:
Heen City: 9600 max
Eykfar: 23800 max
Definately some population disparity between some rurals and cities.