Rafnsdal. A tiny place that has been there forever, grown like a lichen from the most inhospitable, windy, rainy mainland rock its inhabitants could find within a hundred miles. Their grandparents lived on this rainy rock. Their great grandparents. Their great great grandparents before them. Their rainy rockiness grew on them like lichen, too. It's basically their entire identity at this point.
Therefore.. it isn't enough. Oh, no. They must find even worse, even colder, even rainier and foggier rocks. Aka, move out onto the islands.
They shall evolve into super-vikings and make their ancestors proud.
Why? Shh. Let people have hobbies.
Goal: A population of 500 surviving on every island of this logistical nightmare map.