Ongentheow was the name of a semi-legendary Swedish king of the house of Scylfings, who appears in Old English sources.
Illustration by Gerhard Munthe (1899)
Middle royal tumulus at Old Upsala, suggested grave of King Ongentheow/Egil
The Swedes were a North Germanic tribe who inhabited Svealand in central Sweden and one of the progenitor groups of modern Swedes, along with Geats and Gutes. They had their tribal centre in Gamla Uppsala.
Piraeus Lion drawing of curved lindworm. The runes on the lion tell of Swedish warriors, most likely Varangians, mercenaries in the service of the Byzantine (Eastern Roman) Emperor.
The Runestone DR 344 is one of the earliest surviving instances of the name Svíþjóð, in Scandinavia (only Runestone DR 216, Beowulf and probably also the Getica are earlier).
Gamla Uppsala was the main religious and political centre of the tribe.
Gaius Cornelius Tacitus