Beowulf is the hero and title character of an Anglo-Saxon epic poem. The poem was written in England, though the action is set in Scandinavia. Beowulf is among the most important extant Anglo-Saxon works of literature. It takes place in the 5th and 6th centuries CE, but was written some time between the 8th and 11th centuries.

According to the poem, Beowulf was the son of a Swede, Ecgþeow, but grew up among the Geats. Ecgþeow had been banished before Beowulf's birth because he was unable to pay a high weregild, a type of fine imposed on those who had killed a man. Ecgþeow sought refuge with the Danish king Hroðgar, who paid his weregild, then served under Geatish king Hreðel. Ecgþeow married Hreðel's daughter, and Beowulf was their child.

Beowulf began his heroic acts as a young warrior, when a monster named Grendel threatened Hreðel's kingdom. Beowulf killed the monster, ripping of his arm, and was celebrated by his fellow warriors as a hero. The following night, Grendel's mother, who is unnamed in the poem, arrives to avenge his death. Beowulf kills her too, with the help of a magical giant sword, then takes Grendel's head as a trophy back to Geatland.

After these adventures, Beowulf fought for the Geatish throne along side king Hygelac. After Hygelac died during a raid on the Franks, his widow offered Beowulf the throne, but Beowulf declined so that her son Heardred could succeed his father. Heardred later died in a Swedish invasion, and Beowulf finally became king of the Geats.

Beowulf had ruled the Geats for 50 years when a dragon threatened his realm. He battled the dragon and killed it, but also suffered mortal injuries. Before dying, he prophesied that the Swedes would once again attack the Geats. He was buried by his men in a barrow near the sea.

Scholars believe that Beowulf is a mixture of legend and historical reality, but no historical personage has been identified as the literary Beowulf. One theory holds that he is the same figure as Bödvar Bjarki of Scandinavian lore, but this idea is controversial. Beowulf's name literally means "bee-wolf," which may reference a bear, since a bear is like a wolf, or a hunter, of bees. Therefore, Beowulf is probably a literary nickname rather than the given name of a historical king.