### Clue: South American congress assembled ancient kingdom (6)
### Answer: SUSSEX 
 ### Explanation: Definition: ancient kingdom
A charade of S ('south') plus US ('American') plus SEX ('congress'). As the '-sex' bit suggests, the kingdom existed in Saxon times, after the Romans and before the Norman conquest (although the kingdom ceased to be independent long before that, being under first Mercia and then Wessex)