Girl from Spain has to rely on soldiers (7)
I believe the answer is:
eleanor
'girl' is the definition.
'spain has to rely on soldiers' is the wordplay.
'spain' becomes 'e' (abbreviation for Espana).
'has' means one lot of letters go next to another.
'to rely on' becomes 'lean' (I can't explain this - if you can you should give a lot more credence to this answer).
'soldiers' becomes 'OR' (military abbreviation for other ranks).
'e'+'lean'+'or'='ELEANOR'
'from' acts as a link.
Can you help me to learn more?
(Other definitions for eleanor that I've seen before include "woman" , "Wife of F. D. Roosevelt" , "Female" , "-- Bron, actress" , "Name used in Beatles song" .)