The Contentstack app functions at the optimum level in the European region similar to the North American region.
What it isn't
It is an independent data center and therefore doesn't work as the fallback or disaster recovery option for the North America region.
It is not a backup of the North America region and the data stored in the European region cannot be accessed by anyone from the North America region.
You cannot store a part of your organization's content in the European region and the other part in the North American region. If you choose the European data center as your region, all of your organization's data will reside in the European region.
The API endpoints for the North American region will not work for the European region. The European region has its own separate, dedicated API endpoints.