Wiglaf is a young Geatish warrior in Beowulf's retinue who follows him to the barrow where the dragon is lurking. When all of Beowulf's other thanes, or lords, abandon him, Wiglaf remains loyally with his king, encouraging and supporting him. It is only with Wiglaf's help that Beowulf is able to defeat the dragon – Wiglaf's timely sword-stroke gives Beowulf the opportunity to stab the dragon in the side and kill it once and for all. As Beowulf is dying, he gives his golden necklace, called a torque, to Wiglaf, probably symbolizing the transfer of power from the dying king to his chosen successor.
Wiglaf represents courage and loyalty in the face of unbelievable odds. In fact, he's a sort of a reverse-Judas figure. Whereas Judas is the only one of the twelve apostles who betrays Jesus, Wiglaf is the only one of eleven thanes who remains loyal to Beowulf. The implication here is that, even though cowardice and betrayal are immoral, in the world of Beowulf they are far more common than true courage, loyalty, and indifference to death and suffering.
Wiglaf is also similar to the character of Horatio in Hamlet – a minor character who is a friend of the hero and who survives to tell the tale to others after everyone else has died.