Invaders of ancient Rome (5)
I believe the answer is:
goths
'invaders of ancient rome' is the definition.
(I've seen this in another clue)
This is the entire clue.
(Other definitions for goths that I've seen before include "Germanic invaders of Roman empire" , "Ancient Germans who gave their name to a style of architecture" , "Rome's Germanic invaders" , "Tribesmen who brought down the Roman empire" , "A Teutonic people who invaded the Roman Empire" .)