Having role in South Africa's ancient city (6)
I believe the answer is:
sparta
'ancient city' is the definition.
(I know that Sparta is ancient)
'having role in south africa's' is the wordplay.
'having role' becomes 'part' (I am not sure about this - if you are sure you should believe this answer much more).
'in' means one lot of letters goes inside another.
'south africa' becomes 'SA' (abbreviation).
'part' going within 'sa' is 'SPARTA'.
Can you help me to learn more?
(Other definitions for sparta that I've seen before include "Laconic state" , "Ancient country" , "Ancient Greek city known for warlike spirit" , "A strap from an ancient Greek city?" , "Ancient Greek city noted for its austerity" .)