[@Gendarme] Well if you read Vohemia's history, you'd probably know that I've made space for an invasion on whoever claimed the isles. I say it would of happen at least a hundred years ago. The reason for the war could be a claim on region of your main island, or foreign support of a rebellious noble or maybe even a succession crisis, it's really up to you.

Considering you're an Island nation, your people would be good with boats, where mine wouldn't have been so much. So I'd anticipate any war being mostly small vohemian raids with little success in making strategic footholes on the isles.