@Doomer
to be fair at that time when they still haven't been cursed they are already established as a kingdom and they still have the authority over the armies.
At this point I am guessing(optimist), so feel free to ignore, but the heathen who go them cursed was probably sacrificed to pacify the noble households and the succeeding line probably worked hard to maintain their stand as royals with the help of loyalist nobles(probably those who are related to them by family).
However, At present the current prince gave up pacifying the goddess and wants to scheme his way through because he has another power backing him(demon god or some last).
My theory seems a to be stretched thin but I got nothing but that.
I just want to see the smug arrogant schemer dig up his own grave along with the royal family at this point. The only reason the hero isn't giving up this country is because his father died protecting it but if the prince wants to use that against him then our loli mc can establish a new puppet to control the country with the reason "the spirits passed judgement on the non-reflecting cursed royal families"