Defeated king is stern — nothing left in possession (6)

I believe the answer is:

harold

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'defeated king' is the definition.
'harold' can be an answer for 'king' (I've seen this before). I am not certain of the 'defeated' bit.

I don't understand the rest of the clue.

Can you help me to learn more?

(Other definitions for harold that I've seen before include "Hastings casualty" , "Maybe Steptoe" , "Man's name" , "Battle of Hastings loser" , "King of England, January-October, 1066" .)

I've seen this clue in The Guardian.

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