The long Old English heroic poem known to modern audiences as Beowulf is probably the most famous product of the rich literary tradition of Anglo-Saxon England (which flourished in the period c. 650-1100). The poem tells the story of Beowulf, a heroic warrior, and later king, of the Geats (a possibly mythical Scandinavian tribe). The events of the poem are set during the Germanic 'heroic age' - a period stretching from the fourth to the sixth century by modern reckoning but described by the poet simply as geardagas ('days of old').

During the course of the poem, the young Beowulf travels across the sea from his homeland in order to help the Danish King Hrothgar, whose people have suffered for twelve years at the hands (and teeth) of a man-shaped and man-eating creature known as Grendel. Having been graciously received by Hrothgar and promised great rewards, Beowulf awaits Grendel's coming by night in the royal hall Heorot. In a scene of great drama and suspense, the poet describes Grendel's approach out of the misty darkness, his sudden and violent entrance into the hall, and his ferocious hand-to-hand encounter with Beowulf. The hero is, of course, victorious, and the fight ends with Beowulf ripping off Grendel's arm at the socket and with Grendel fleeing back into the darkness, mortally wounded. The relief that this victory brings to the Danes is, however, short-lived, as the very next night Grendel's (unnamed and previously unmentioned) mother attacks the hall and kills one of Hrothgar's chief counsellors by way of revenge for her dead son. Once again, Beowulf is called into action, this time going on the offensive and descending through a mere into a subterranean cave-like hall to fight and ultimately kill this ferocious woman (described in the text as ides aglæcwif - 'a lady, a fearsome woman').

Beowulf's exploits amongst the Danes take up most of the first two-thirds of the 3,182 lines of the poem. In the remainder of the poem, Beowulf returns home to the Geats, where his hard-won glory is celebrated and rewarded by his uncle King Hygelac. Fifty years pass, and Beowulf, now an old man, is king of the Geats when his people are menaced by a fire-breathing dragon. Roused once more to heroic action, Beowulf leads an expedition to the dragon’s barrow, where he intends to fight the creature in single combat (as in the days of his youth and glory). The old king is, however, overmatched in his final battle. Seized by the neck in the dragon's mighty jaws, Beowulf is able to win victory only with the help of his young kinsman Wiglaf and at the cost of his own life. The poem ends in elegiac mood, as celebration of Beowulf's heroism mingles with lament for his death and with fearful predictions regarding the fate of his people.

Such a bare summary makes the plot and structure of the poem sound straightforward, but one of the distinctive characteristics of the artistry of Beowulf is the way in which the poet skilfully moves backwards and forwards along a linear narrative timeline, interweaving the main events of the poem with a plethora of inset and secondary narratives. Foreground and background merge in this consummate example of so-called 'interlace' structure, so that the exploits of Beowulf himself are inextricably immersed within a richer background of heroic legend. The success of this narrative technique is one of the many astounding features of the poem. Although many of the events and characters mentioned in Beowulf (including both Hrothgar and Hygelac) are more or less familiar from other early medieval written sources, Beowulf himself is not mentioned elsewhere. It seems likely that the narrative core of the poem was the invention of the Anglo-Saxon poet, part of whose achievement was to 'place' this new narrative material so seamlessly within the wider corpus of Germanic legendary history.

The individual responsible for this remarkable achievement has remained elusive. Beowulf survives in a single manuscript copy (now held in the British Library: Cotton MS Vitellius A.xv), probably produced around about the year 1000. Beyond this fact, however, the poem's origins are obscure. Like most English verse from this period, the poem is anonymous, and the approximate date of composition has long been a topic of (sometimes acrimonious) debate amongst scholars, with estimates ranging from the mid seventh to the early eleventh century. Faced with such a lack of solid evidence, we can deduce little about the circumstances in which the poem was produced. Like other surviving Old English poems (though to an even greater degree), the language of Beowulf is marked simultaneously by an astonishingly creative and poetic verbal inventiveness - particularly evident in the use of uniquely-occurring descriptive compound words - and by a layer of verbal formulas and 'type scenes' which recur both throughout the poem and throughout the surviving corpus of Old English poetry. These latter features, which may seem dangerously close to cliché for a modern audience, point to the ultimate origins of Old English poetry in an essentially pre-literate, oral, and performative tradition. It seems unlikely, however, that Beowulf is itself in any real sense an oral composition. Most scholars today would accept that the poem is (very largely if not entirely) the product of a single poetic vision, the work of a literate and Christian poet probably working within a monastic or courtly milieux.

That the poet was a Christian writing for a Christian audience is clear. Grendel, for example, is explained by the poet-narrator as a diabolical descendant of Cain, the first murderer, from whose off-spring, according to the Old Testament and to Judeo-Christian Apocrypha, arose the various races of giants. This contextualizing knowledge is not shared, however, by the characters who inhabit the heroic world of the poem. Looking back to the heroic age, the poet is looking back into the pre-Christian Germanic past of the Anglo-Saxon people. The assumed Christian perspective and beliefs of the poet and audience stand in uneasy juxtaposition to the ill-defined but definitely pre-Christian and fatalistic beliefs of the characters themselves. Beowulf, Hrothgar, and other actors in the poem often frame their behaviour in terms of a moral imperative that in many ways approximates the basic tenets of Christianity, but, ignorant of the teachings of Christ, their perspective is limited by the reach of human life on earth. According to Beowulf himself, fame amongst men is the best that can be hoped for a dead warrior:

'Ure æghwylc sceal ende gebidan
worolde lifes; wyrce se þe mote
domes ær deaþe; þæt bið drihtguman
unlifgendum æfter selest.'

(Beowulf 1386-89, 'Each of us must await the end of life in the world. Let he who may achieve glory before death - that will afterwards be best for the dead warrior.')

The poignant irony of such a statement could not have been lost upon an audience for whom life in the world was merely a precursor to the eternal reward (or punishment) to be experienced in the world to come.

As an Old English poem, Beowulf is a unique and incomparable literary artefact - the only known surviving example of the efforts of a supreme master working within a mature and remarkably long-lived poetic tradition. Its superlative poetic qualities have been recognized by generations of modern readers, and there is increasing evidence to suggest that Beowulf was both widely known amongst and frequently imitated by other Anglo-Saxon poets whose work also survives. There are, to be sure, difficulties associated with the appreciation of the poem today. Most notably, modern readers must overcome the barrier caused by the language of the poem, recognizably English but a form of English in use a thousand years before our own time. But such barriers are far from insuperable, especially given the availability of many excellent and sympathetic modern translations. The effort is well-rewarded. We need not seek an excuse to read and study Beowulf today; the poem is its own best justification.