Antoine's resolved to be European (8)
I believe the answer is:
estonian
'be european' is the definition.
(person from Estonia)
'antoine's resolved' is the wordplay.
'resolved' indicates anagramming the letters.
'antoines' with letters rearranged gives 'ESTONIAN'.
'to' acts as a link.
(Other definitions for estonian that I've seen before include "Person from Tallinn, say." , "Northern European" , "Eg, native of Tallinn" , "One from a Baltic state" , "E. European" .)