Fictional Amerindian soldiers leaving Canadian city (5)
I believe the answer is:
tonto
'fictional amerindian' is the definition.
(tonto matches up with the definition fictional amerindian)
'soldiers leaving canadian city' is the wordplay.
'soldiers' becomes 'OR' (Other Ranks).
'leaving' suggests deleting specific letters.
'canadian city' becomes 'Toronto' (Toronto is a city in Canada).
'toronto' with 'or' taken out is 'TONTO'.
(Other definitions for tonto that I've seen before include "Western companion" , "The Lone Ranger's sidekick" , "Faithful companion" , "Lone Ranger and - -" , "The Lone Ranger's companion" .)