If you recall, Alene was created in a volcanic eruption, which was why she shared a body with her 2P.

Now, after extensive research, I learned, that the rocks her Islands are made of are a kind of basalt made from the lava from a lava field underneath the North Atlantic Ocean. The same sort of basalt can be found in parts of Ireland and Scotland.

The lava field was, as can be read, active in the Paleogene time period.

That lava field was active 60-23 million years ago.
Which means Faroe Islands has to have been created during that time. Faroe has been in her current form for over 23 million years.

Meaning that she was created as soon as the homo sapiens sapiens started to exist, about 200000 years ago.

However, back then, no-one inhabited her islands. She fell into a coma, because her health was too frail to actually be able to keep her alive. She was in that coma for the longest time, until Scotland found her. The coma she fell in was enough of a shock for her to create her 2P, as she almost immediately fell in it when she was born, because of her disability to breathe, eat, drink and digest normally. Her body didn't age in the coma, but her intellect did, which is why she has a great understanding of the world. Though she can act a bit childish at times, she knows her place and that is the oldest sister of the Danish household.

She did get her asthma from volcanoes, but that could also have been because she's relatively close to Iceland.

Due to her magic, when everyone claimed her again and again, her appearance changed, though she always kept a green eye and brown hair.

So, by ground (which could be interpreted as 'by blood'), she's related to Scotland, Ireland, Northern Ireland, Greenland, Norway, and Iceland. By family, she's related to Norway, Iceland, and Denmark, though she also counts Scotland part of her family.