Dictionary of National Biography, 1885-1900/Sebert
SEBERT, SABERET, or SABA (d. 616?), first Christian king of the East-Saxons, son of Sledda, king of the East-Saxons, by his wife Ricula, sister of Ethelbert or Æthelberht (552?–616) [q. v.], king of Kent, reigned in dependence on his uncle Ethelbert, and became a Christian soon after the latter's conversion. He and his people received Mellitus [q. v.] as their teacher and bishop. The founder of St. Paul's Church in London, the chief city of the East-Saxons, was, however, not Sebert, but his superior king, Ethelbert. Sebert is said to have founded Westminster Abbey, but this is a late legend. He died soon after Ethelbert, in or about 616, and was succeeded by his three sons, who had remained heathen, and under whom the East-Saxons relapsed into heathenism [see under Sexred]. In 1308 a tomb, said to be that of Sebert, was opened in Westminster Abbey for the purpose of translating the relics, and the right hand and forearm of the body were found undecayed.
[Bede's Hist. Eccl. ii. cc. 3, 5; A.-S. Chron. an. 604, ed. Plummer; Kemble's Codex Dipl. No. 555 (Engl. Hist. Soc.); Monasticon, i. 265, 288–91; Ann. Paulini ap. Chron. Edw. I and Edw. II, i. 266 (Rolls Ser.); Dict. Chr. Biogr. art. ‘Sebert,’ by Bishop Stubbs.]