Constant rallies disrupted city (8)
I believe the answer is:
carlisle
'city' is the definition.
(English city)
'constant rallies disrupted' is the wordplay.
'constant' becomes 'C' (mathematical abbreviation).
'disrupted' indicates an anagram.
'rallies' anagrammed gives 'arlisle'.
'c'+'arlisle'='CARLISLE'
(Other definitions for carlisle that I've seen before include "England's Border City" , "County town of Cumbria" , "Cumbrian city where Royalists surrendered in 1645" , "cathedral city" , "Cellars I turn to in Northern English city" .)