Hogan's domain (6)
I believe the answer is:
'hogan's domain' is the definition.
(I've seen this in another clue)
This is all the clue.
(Other definitions for stalag that I've seen before include "German POW camp in WWII" , "German prison_camp" , "German concentration camp" , "Type of German prison camp" , "German prisoner-of-war camp of WW2" .)