Historian American names in top celebrity category (8)
I believe the answer is:
annalist
'historian' is the definition.
(annalist is a kind of historian)
'american names in top celebrity category' is the wordplay.
'american' becomes 'a' (common abbreviation - e.g. in organisation names).
'names' becomes 'nn' (an abbreviation for name twice).
'in top celebrity category' becomes 'alist' (I can't explain this - if you can you should give a lot more credence to this answer).
'a'+'nn'+'alist'='ANNALIST'
Can you help me to learn more?
(Other definitions for annalist that I've seen before include "Narrator" , "One making records" , "Historian" , "Chronicler" , "Person creating records" .)