Tree hiding English kings in Civil War battle (9)
I believe the answer is:
naseberry
'tree' is the definition.
(I know that naseberry is a type of tree)
'hiding english kings in civil war battle' is the wordplay.
'hiding' is an insertion indicator.
'english' becomes 'E' (abbreviation).
'kings' becomes 'RR' (abbreviation for rex - 'king' in Latin - repeated).
'in' indicates putting letters inside.
'civil war battle' becomes 'naseby' (I've seen this before).
'rr' put within 'naseby' is 'nasebrry'.
'e' placed within 'nasebrry' is 'NASEBERRY'.
(Another definition for naseberry that I've seen is " Tree".)