People from Zagreb, perhaps, overthrowing Castro (6)

I believe the answer is:

croats

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'people from zagreb' is the definition.
I don't know anything about this answer so I can't tell whether this works.

'overthrowing castro' is the wordplay.
'overthrowing' indicates anagramming the letters (I've seen 'overthrown' mean this).
'castro' is an anagram of 'CROATS'.

'perhaps' is the link.

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