Oswald was an Ealdorman of Sussex, jointly with three former kings: Osmund, Ælfwald, and Oslac.
He witnessed a charter of Offa, King of Mercia, dated 772 as Osuualdus dux Suðsax'.
[1] He was listed ahead of the three former kings Osmund, Ælfwald, and Oslac, which implies that his rank was higher.
However, this is mere speculation; there is no actual evidence that Oswald ever reigned as king.
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