This is not a usual scenario. In general views should not be aware in which region they are located nor regions know their parent views. There are of course tricks to get what you are looking for
but you will be probably breaking modularity or coupling modules.
If what you are looking for is a way to share some contextual information between the region and its children, you should use the RegionContext. You can find more information on how to use
the RegionContext in the Communication and UI
Composition Technical Concepts of the documentation.
To get the region in which a view is defined you can do something like the following:
IRegion region = regionManager.Regions.First(r => r.Views.Contains(yourView));
You can obtain a reference to the regionManager using
dependecy injection. You might find useful the
How to: Show a View in a Scoped Region
If you what to get the WPF control that the region is mapped to, you can generally query the view's
Parent property (That is equivalent to using the LogicalTreeHelper.GetParent method):
ContentControl control = view.Parent;
Hope it helps!