"Splunk Cloud is primarily available in the Amazon Web Services (AWS) US Virginia region. If you require your data to be co-located, there are global data centers in the US (Virginia, California, Oregon), EU (Dublin, Frankfurt), Asia Pacific (Singapore, Sydney, Tokyo), and South America (São Paulo)."
I am unable to find documentation stating the option of storing your data only in one region. Could you please help point me in the right direction to find this information.
Splunk cloud instances are built in single regions only. They do not span multiple aws regions, unless you buy multiple instances.
I recently worked with a client with the same requirements and they chose to host their indexers and searchheads in Dublin.
I'll see if I can rustle up documentation to that effect, but I speak from experience.