All British Cast?

[Steve]

When they decided or as someone implied JKR insisted on an all British
cast, was that meant literally, or was it indended to mean the
characters have to be from or related to the country of origin for the
charaters they are playing?

Does Victor Krum have to come from a short list of young British
actors,  or does the 'all British' rule imply that Victor has to be an
actor from Bulgaria (Germany, Austria, eastern Europe, Russia), and
Fleur Delacour has to be from France? 

And Cho Chang, does she have to be British, or simply Asian,
persumably Chinese?

Then I must ask what qualifies as British? Canada? Australia? New
Zealand? These are or were a part of the British Empire at one time.

Of course, we probably can't know for sure, but I'm  still interested
in your opinions.

bboy_mn