The peace subsequently includes the French (7)
I believe the answer is:
silence
'the peace' is the definition.
(I've seen this before)
'subsequently includes the french' is the wordplay.
'subsequently' becomes 'since' (I've seen this in another clue).
'includes' means one lot of letters goes inside another.
'the french' becomes 'le' ('the' in French).
'since' placed around 'le' is 'SILENCE'.
(Other definitions for silence that I've seen before include "What's left of burnt coal" , "'The rest is - - '(Hamlet)" , "Quiet" , "License (anag)" , "It is golden acccording to the 1960s song" .)