Theory:
combination of the WORLDPKGDESC file describing the settlement size and faction that built it along with desc_strat detailing what settlement size and founding culture each custom settlement is.
Anything else im missing that holds it all together? And what program am I supposed to use to view/edit the worldpkgdesc files? I just opened and read it with notepad...
New questions:
Which file governs the terrain type of a city? What if I wanted to make Minas Morgul pretty grassland and trees like it was when it was Minas Ithil, back in the day?
Which file(s) determine(s) what a city looks like on the campaign map?