The first time I saw the photo it had a reference of Ickworth in England but never was able to find an original image source or other photos of the interior.Hopefully you will unearth something.
Thank you so much FleaingFrance and Henhurst Interiors . Will google both right now! Phil xxxx
I believe it is Kedleston Hall in Derbyshire.
It is in the Kedleston Hall. My favorite movie The Duchess was filmed there.http://www.flickr.com/photos/42170344@N07/galleries/72157625225714529
Interestingly, there is a space at George Washington's Mt. Vernon that resembles this very much. (Obviously on a much smaller scale). I wonder whether there was inspiration there?