What ancient Lombardic king, used by J. R. R. Tolkien, has a grandson named Beowa?
Beowa:  The figure is attested in the Anglo-Saxon royal genealogies as they were extended in the age of Alfred, where Beowa is inserted as the son of Scyld and the grandson of Sceafa, in lineages carried back to Adam. Sceafa: Sceafa (Old English: "Scēafa" ] , also spelled "Scēaf", "Scēf") was an ancient Lombardic king in English legend. Sceafa:  Though the name has historically been modernized Shava (and Latinized Scefius), J. R. R. Tolkien used the modern spelling "Sheave".
Sceafa