It was quite obvious Caligus would lose to Perdan. Caligus has mountains and wastelands. Perdan has townslands and rurals.
Well that's a bit of an overgeneralization but close enough.
I think there many other factors that have allot more influence, like good leadership, a decent number of good active nobles and geographical position of the capitals of the parties involved.
Just rich regions brings you nowhere without nobles that can take estates there, actually recruit and fight battles.
