[CK2 MODDING] What is custom, and how Can I modify it?

[BeeDate]

I dont understand what for example “region = custom_england” means, and why it cant be something like “region = k_england”.
So yeah, my question is, what does it mean exactly, and how Can I modify it?

 

[Keizer Harm]

Regions are not the same as kingdoms. They are separate from them, and while the custom_ prefix is not one I would choose, it is simply what that one happens to be called. See the complete list in map/geographical_regions.txt

 

[BeeDate]

Yea I figured out that it was the regions you see When you click On that green tab you see When you have a province window open.
So the simple fix was to just make iceland it’s own region