Dark Sky Map
If you want to know what areas are sparsely populated, this is the way to check.
Sparsely populated areas have darker skies at night.
Teruel, Spain has some of the darkest skies in Europe, so it is indeed sparsely populated. There are some areas in SE Netherlands that are darker than the rest of the country, but over all, it's pretty bright there. Poland has some empty areas with dark skies.
The problem is, if the area is sparse enough to have dark skies, a lot of times there isn't even a close enough town to offer stores, and a decent pub. You have to really want a remote area to really live there.
Yup see my post a page or so ago. Teruel in fact is one of the least populated areas in all of Europe: 9.x people per square km which is roughly 24 people per square mile. The US has 92 inhabitants per square mile, just to give you a frame of reference.
And a store or supermarket is probably less than an hour away on average, that's doable.