Romantic song in series English and European backed (8)
I believe the answer is:
serenade
'romantic song' is the definition.
'series english and european backed' is the wordplay.
'series' becomes 'ser' (abbreviation for series).
'english' becomes 'E' (abbreviation).
'and' says to put letters next to each other.
'european' becomes 'dane' (someone from Denmark).
'backed' is a reversal indicator.
'dane' in reverse letter order is 'enad'.
'e' after 'enad' is 'enade'.
'ser'+'enade'='SERENADE'
'in' is the link.
(Other definitions for serenade that I've seen before include "Music appropriate for evening" , "Song of romance" , "(Romantic?) song or tune" , "Song often sung under a window" , "Play music, sing for someone" .)