European victory by pleasant Italian city (6)
I believe the answer is:
venice
'italian city' is the definition.
(I've seen this in another clue)
'european victory by pleasant' is the wordplay.
'european' becomes 'E' (abbreviation e.g. EU).
'victory' becomes 'v'.
'by' says to put letters next to each other.
'pleasant' becomes 'nice' (similar in meaning).
'e' put after 'v' is 've'.
've'+'nice'='VENICE'
(Other definitions for venice that I've seen before include "Messages" , "City of 15 acrosses" , "La Serenissima" , "Italian city port" , "Italian city once known as Queen of the Adriatic" .)