The Spear-Danes are the Scyldings (Hrothgar's tribe)--central characters in Beowulf. They are variously referred to as Beorht-Dene (Bright-Danes), Éast-Dene (East-Danes), Gár-Dene (Spear-Danes), Hring-Dene (Ring-Danes), Norð-Dene (North-Danes), Súð-Dene (South-Danes), West Dene (West Danes), Scyldings (after their eponymous founder) and Ingwine (lit. 'friends of Ing [=OE. Frea / ON. Freyr ]')

This is a different Beowulf from the eponymous hero of the poem. This is Béowulf Scyldinga or Béowulf the Dane, presumably equivalent to Beow(a) or Béaw of the geneaologies:-- the Parker MS of the Anglo-Saxon Chronicle has Beaw as the son of Scyld.