French people inhabiting cabin or mansion (7)
I believe the answer is:
normans
'french people' is the definition.
(people from Normandy)
'inhabiting cabin or mansion' is the wordplay.
'inhabiting' says the answer is hidden in the clue.
'NORMANS' is hidden within 'cabin or mansion'.
(Other definitions for normans that I've seen before include "Invaders in 1066" , "William the Conqueror's lot?" , "They won the battle of Hastings" , "some French people" , "11th century invaders" .)