One about to settle in the country (7)
I believe the answer is:
ireland
'the country' is the definition.
(Ireland is a country)
'one about to settle' is the wordplay.
'one' becomes 'I' (Roman numeral).
'about' becomes 're' ('re' means regarding or about).
'to settle' becomes 'land'.
'i'+'re'+'land'='IRELAND'
'in' is the link.
(Other definitions for ireland that I've seen before include "music's John" , "European country" , "British composer" , "Eire" , "See 10" .)