Revolutionary purge consuming a capital (6)
I believe the answer is:
prague
'capital' is the definition.
(capital of Czechia)
'revolutionary purge consuming a' is the wordplay.
'revolutionary' is an anagram indicator.
'consuming' is an insertion indicator.
'purge' with letters rearranged gives 'prgue'.
'prgue' going around 'a' is 'PRAGUE'.
(Other definitions for prague that I've seen before include "Capital city of Czech Republic" , "European capital" , "Czech Republic's capital" , "Gear up for this European city" , "Rather quiet" .)