Rome reps travelling for those expanding into new territories (8)

I believe the answer is:

emperors

I'm a little stuck... Click here to teach me more about this clue!

'those expanding into new territories' is the definition.
I can't tell whether this defines the answer.

'rome reps travelling' is the wordplay.
'travelling' indicates anagramming the letters.
'rome'+'reps'='romereps'
'romereps' with letters rearranged gives 'EMPERORS'.

'for' is the link.

Can you help me to learn more?

(Other definitions for emperors that I've seen before include "Rulers of great territories" , "Tsars" .)

I've seen this clue in the Irish Times.

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