Hold sway in Niger, maybe (5)
I believe the answer is:
reign
'hold sway' is the definition.
(I've seen this before)
'niger maybe' is the wordplay.
'maybe' indicates anagramming the letters.
'niger' anagrammed gives 'REIGN'.
'in' is the link.
(Other definitions for reign that I've seen before include "Niger (anag)" , "Period of monarch" , "Monarch's rule" , "Prevail" , "Wield the sceptre" .)