Here is a note from Smartsheet regarding their API in the EU region:
Smartsheet Regions Europe is a separate data island. As an API developer working on a Smartsheet Regions Europe account, you should be aware of the following differences from the standard API:
- The base URL for each API call is Smartsheet.eu instead of smartsheet.com. The API documentation uses smartsheet.com in all examples.
- Smartsheet Regions EU uses a separate token from Smartsheet .com.
- If you use a Smartsheet SDK, you must modify the standard config file to point to Smartsheet.eu.