Beowulf is an Old English epic poem consisting of 3182 alliterative lines.

The poem is set in Scandinavia. Beowulf, a hero of the Geats, comes to the aid of Hrothgar, the king of the Danes, whose mead hall in Heorot has been under attack by a monster known as Grendel. After Beowulf slays him, Grendel's mother attacks the hall and is then also defeated. Victorious, Beowulf goes home to Geatland (Götaland in modern Sweden) and later becomes king of the Geats. After a period of fifty years has passed, Beowulf defeats a dragon, but is fatally wounded in the battle. After his death, his attendants cremate his body and erect a tower on a headland in his memory.

The main protagonist Beowulf, a hero of the Geats, comes to the aid of Hrothgar, king of the Danes, whose great hall, Heorot, is plagued by the monster Grendel. Beowulf kills Grendel with his bare hands and Grendel's mother with a giant's sword that he found in her lair.

Later in his life, Beowulf becomes king of the Geats, and finds his realm terrorized by a dragon, some of whose treasure had been stolen from his hoard in a burial mound. He attacks the dragon with the help of his thegns or servants, but they do not succeed. Beowulf decides to follow the dragon to its lair at Earnanæs, but only his young Swedish relative Wiglaf, whose name means "remnant of valour",[a] dares to join him. Beowulf finally slays the dragon, but is mortally wounded in the struggle. He is cremated and a burial mound by the sea is erected in his honor.

Beowulf is considered an epic poem in that the main character is a hero who travels great distances to prove his strength at impossible odds against supernatural demons and beasts.