Rome's commoner people brought sandwiches (4)
I believe the answer is:
pleb
'rome's commoner' is the definition.
'pleb' can be an answer for 'commoner' (pleb is a kind of commoner). I am unsure of the 'rome's' bit.
'people brought sandwiches' is the wordplay.
'sandwiches' says the answer is hidden in the clue (the solution is sandwiched in by the clue).
'PLEB' is hidden within 'people brought'.
Can you help me to learn more?
(Other definitions for pleb that I've seen before include "Person of vulgar tastes (colloq.)" , "Boor" , "Uncultivated type" , "Commoner" , "Common guy" .)