Tyrant of French location (6)
I believe the answer is:
despot
'tyrant' is the definition.
(I know that tyrant can be written as despot)
'of french location' is the wordplay.
'of french' becomes 'de' ('of' in French).
'location' becomes 'spot' (spot is a kind of location).
'de'+'spot'='DESPOT'
(Other definitions for despot that I've seen before include "Arbitrary ruler" , "Tyrant, slave driver" , "Autocrat" , "Tyrant, dictator" , "Caesar for one" .)