Rupert —, war poet (6)
I believe the answer is:
brooke
I believe this is a double definition.
'rupert' is the first definition.
(I've seen this before)
'war poet' is the second definition.
(I've seen this before)
(Other definitions for brooke that I've seen before include "Rupert --, English war poet" , "Rupert --, WW1 poet" , "Versifying Rupert" , "See 1" , "one called Rupert" .)