In Beowulf, warrior culture is closely associated with the mead hall and, through the mead hall, with civilization itself. The Beowulf warriors congregate in the mead hall, a place of physical warmth, hospitality, and safety. In the mead hall, there is ample food and drink, friendship, and a place to put one's weapons. It is the bulwark protecting society against the fierce onslaught of nature.
In this poem, nature is associated with the frightening, uncertain, dangerous, and bestial—it is not the pleasant place of butterflies and dancing daffodils that it will become in literature hundreds of years later. Instead, it is a place of ominous bogs and marshes, and most especially, the home of monsters like Grendel and his mother.
The deep horror of Grendel's attacks on Heorot rests on the fact that Grendel is upending the heart of the civilized world. Heorot is both the symbol of the male warrior culture and the symbol of civilization itself. With its timbered support beams and gold ornamentation, the place is described as "the foremost of halls under heavens." If the male warrior culture can't successfully defend this most radiant emblem of civilization from nature's barbarous encroachments, civilization itself threatens to dissolve.
Beowulf himself, of course, comes to the rescue and is the exemplar of the warrior culture: brave, loyal, good, exceptionally strong, and willing to sacrifice himself to protect civilization.
The poem reflects social conditions of a time in which civilization clung precariously to life amid multiple threats. The strength and bravery of the warrior was important to protecting this culture, and the society was inward directed, banding together to protect itself against outside threats.