Primitive and others to surround the French soldiers (9)
I believe the answer is:
elemental
'primitive' is the definition.
('elemental' can be a synonym of 'primitive')
'and others to surround the french soldiers' is the wordplay.
'and others' becomes 'etal' ('et al.' can be a synonym of 'and others').
'to surround' is an insertion indicator.
'the french' becomes 'le'.
'soldiers' becomes 'men' (I've seen this before).
'le'+'men'='lemen'
'etal' enclosing 'lemen' is 'ELEMENTAL'.
(Other definitions for elemental that I've seen before include "Let me lean like forces of nature" , "Basic, primitive" , "being like Mercury?" , "of fire, say" , "Fundamental; supernatural entity" .)