Old European kingdom, some feel it's a country on the rise (7)
I believe the answer is:
castile
'old european kingdom' is the definition.
(Castile is a former European kingdom)
'some feel it's a country on the rise' is the wordplay.
'some' indicates a hidden word (some of the parts of the word are used).
'on the rise' is a reversal indicator (in a down clue, letters go up).
'elitsac' is hidden within 'feel its a country'.
'elitsac' written backwards gives 'CASTILE'.
(Other definitions for castile that I've seen before include "Old Spanish kingdom" , "Elastic region in central Spain" , "Elastic (anag) -- region of Spain" , "former Spanish kingdom" .)