Looking for the inspirations for a plot connected to a few domains

I'm preparing to run a campaign in Ravenloft (using SWADE and Ravenloft Reincarnated as a base).
This version is mostly based on 2e/3e lore, but divides Core into smaller clusters. We had session zero, and decided to run campaign centered around Kartakass, and other domains in cluseter- which are Valachan, Vebrek and Arkandale, which RR interprets as a kinda american south pre civil war.

And I'm doing my research about this cluster. Are there any major plot points that happened in the region, and were mostly closed in these domains.

I know that Feast of Goblyns happens in large parts in Kartakass, but it also involves Gundarak, which I'd like to avoid (and it skips rest of the region).

I'm looking for any plots or inspirations that could help me connect elements between these domains.

Thanks in advance!