Life in Paris before Napoleon evacuated a capital city (6)
I believe the answer is:
vienna
'capital city' is the definition.
(capital of Austria)
'life in paris before napoleon evacuated a' is the wordplay.
'life in paris' becomes 'vie' ('life' in French).
'before' is a charade indicator (letters next to each other).
'evacuated' means to remove the middle letters.
'napoleon' with its middle taken out is 'nn'.
'vie'+'nn'+'a'='VIENNA'
(Other definitions for vienna that I've seen before include "Capital on the Danube Canal" , "Adult home of Beethoven, Brahms, Mozart and Schubert" , "Capital city of Austria" , "Austria's capital city" , "City of Strauss and the waltz" .)