Territory no good party covered in imperialistic work (7)
I believe the answer is:
kingdom
'territory' is the definition.
(kingdom is a kind of territory)
'no good party covered in imperialistic work' is the wordplay.
'no' becomes 'n' (common abbreviation).
'good' becomes 'g' (abbreviation).
'party' becomes 'do' (do is a kind of party).
'covered in' is an insertion indicator.
'imperialistic work' becomes 'kim' (Rudyard Kipling novel).
'n'+'g'+'do'='ngdo'
'ngdo' put within 'kim' is 'KINGDOM'.
(Other definitions for kingdom that I've seen before include "Monarchical state" , "Regal realm" , "Major category of biological classification" , "Domain of royal ruler" , "big territory?" .)