Æðelstan was a King, presumably of Sussex

Kingdom of Sussex

The Kingdom of Sussex or Kingdom of the South Saxons was a Saxon colony and later independent kingdom of the Saxons, on the south coast of England. Its boundaries coincided in general with those of the earlier kingdom of the Regnenses and the later county of Sussex. A large part of its territory...

, reigning jointly with Noðhelm

Nothelm of Sussex

Noðhelm, or Nunna for short, was King of Sussex, apparently reigning jointly with Watt, Osric, and Æðelstan.-Life:Kelly noted the names of rulers in Sussex starting with Aethel- and Os- and suggested they might have been relatives. She also referred to the King list of Hwicce in this respect and...

.

He witnessed Noðhelm

Nothelm of Sussex

Noðhelm, or Nunna for short, was King of Sussex, apparently reigning jointly with Watt, Osric, and Æðelstan.-Life:Kelly noted the names of rulers in Sussex starting with Aethel- and Os- and suggested they might have been relatives. She also referred to the King list of Hwicce in this respect and...

’s last surviving charter, which is dated 714 in error for 717, as Athelstan rex. There is no indication of his kingdom. The same charter was also witnessed by Queen Æðelðryð, as Edeldrið regina, presumably the Æðelstan's wife. Barker (1947) speculated "They may well be the parents of the Æðelberht

Aethelbert of Sussex

Aethelbert, or, more correctly, Æðelberht, was King of Sussex, but is known only from charters. The dates of Æðelberht’s reign are unknown beyond the fact that it overlapped at least in part with the bishopship of Sigeferth of Selsey, as Sigeferth witnessed an undated charter of Æðelberht in which...

of twenty years later".