A campaign seed
In Theah in late 1668... well, in late 1668 we're into canonical spoiler territory, so let's put this below the cut. It's an idea for a major event that could frame an Eisen-Castillian campaign.
In late 1668, Leon of Montaigne is dead and Castille and Montaigne are negotiating peace. Eisenfurst Erich Sieger is leading his mercenary troops through Vodacce. Cardinal Verdugo is still a major power in Castille.
The War of the Cross ended with the Treaty of the Weissbergs, which granted Sieger's lands to Castille. That's when he sowed them with salt and vowed to fight to the last man. Castille never really pursued the matter.
In his absence, Sieger has left his Iron Guard, the infamous Morderbande, in charge. The people of Sieger are terrified of them and hate them.
But south Eisen is also Objectionist. A Castillian invasion, spearheaded by the Inquisition, is hardly the rescue they've been dreaming of.
Sieger's people have been betrayed by their overlord, forced into poverty and starvation, terrorized by the thuggish Morderbande and now may face losing either their Objectionist faith or their lives. It's a time and a place where a determined band of heroes could stand up to create a third option for the people of Sieger.