An artist somehow seems to be king (7)
I believe the answer is:
rameses
'be king' is the definition.
(I've seen this before)
'an artist somehow seems' is the wordplay.
'an artist' becomes 'RA' (Royal Academician, member of Royal Academy of Arts).
'somehow' is an anagram indicator.
'seems' is an anagram of 'meses'.
'ra'+'meses'='RAMESES'
'to' acts as a link.
(Other definitions for rameses that I've seen before include "See Mars (anag) - Pharaoh" , "old ruler?" , "Egyptian pharaoh" , "One of several pharaohs" , "Mere ass (anag) - one of eleven pharaohs" .)