Scot meets English fellow in ancient territory (7)
I believe the answer is:
macedon
'ancient territory' is the definition.
(Macedon was an ancient kingdom)
'scot meets english fellow' is the wordplay.
'scot' becomes 'mac' (many Scottish surnames begin with Mac).
'meets' means one lot of letters go next to another.
'english' becomes 'E' (abbreviation).
'fellow' becomes 'don' (both can mean an academic).
'mac'+'e'+'don'='MACEDON'
'in' acts as a link.
(Other definitions for macedon that I've seen before include "Philip's place" , "Alexander the Great's country" , "Philip's rule" , "Kingdom of Alexander the Great" .)