An actor I cast, European (8)
I believe the answer is:
croatian
'european' is the definition.
(I've seen this before)
'an actor i cast' is the wordplay.
'cast' indicates an anagram (letters are dispersed or cast around).
'an'+'actor'+'i'='anactori'
'anactori' is an anagram of 'CROATIAN'.
(Other definitions for croatian that I've seen before include "Split personality" , "European native" , "Raincoat (anag.)" , "from area in Europe" , "Native to a Balkan republic that became independent in 1991" .)