It's apparently possible to win by having the highest score when the turn limit is reached (and there's a Steam achievement for it). How many turns is the turn limit? Is it dependent on the size of the map?
I found an old post on the forum from the beta that said it was controlled by a game setting, but I can't find the setting referred to.
Edit: BTW, I searched the pdf manual that came with the game and the Hiergamenon, and neither mentioned the turn limit win.