A despot in foreign, diametrically opposite territories (9)
I believe the answer is:
antipodes
'diametrically opposite territories' is the definition.
(places on opposite sides of the Earth)
'a despot in foreign' is the wordplay.
'foreign' indicates anagramming the letters (foreign order of the letters).
'despot'+'in'='despotin'
'despotin' anagrammed gives 'ntipodes'.
'a'+'ntipodes'='ANTIPODES'
(Other definitions for antipodes that I've seen before include "places poles apart?" , "Regions on diametrically opposite sides of the Earth" , "Australia and New Zealand viewed from Europe" , "Places that are on opposite sides of the world" , "Distant places" .)