Sir Gawain
The protagonist of the poem, Sir Gawain is the central figure whose fundamental character change forms the focus of the work. At the start of the poem he is an eager, optimistic, and loyal knight who undertakes the Green Knight's challenge to protect Arthur and preserve the reputation of Camelot. By the end, he has come to question the viability of the chivalric code and realize the weakness in his own human nature. Ultimately, it is his instinctive fear of mortality which comes in conflict the societal values he has learned and it is this conflict which leaves Gawain feeling troubled at the poem's close.
By all societal standards, Gawain is seen as the epitome of chivalry, as illustrated by his deferential speech to Arthur when he accepts the Green Knight's challenge: "My life would be least missed, / if we let out the truth. / Only as you are my uncle have I any honor, / For excepting your blood, I bear in my body slight virtue" (Gardner ll.555-7). Here he demonstrates the chivalric values of selfless loyalty to one's king and one's relative, and it is this strong sense of chivalry that serves as the catalyst for Gawain's adventure. Central to our understanding of Gawain's character is his shield, marked on the inner side by the image of the Virgin and on the other by the Pentangle. The Pentangle represents the five ways in which Gawain is seen as a flawless character who embodies Franchise, Fellowship, Cleanness, Courtesy, and Charity: "Like purified gold, Sir Gawain was known for his goodness, / All dross refined away, adorned with virtues" (Gardner ll. 634-5). And the image of the Virgin on the inside signifies the religious faith which Gawain uses as his inner protection.
Indeed, much of Gawain's virtue rests in his religious piety, from which he gains the strength to endure his ordeals. As he wanders through a desolate Waste Land, Gawain is the "servant of God" and finds his strength in talking to God (ll. 692-711). On the brink of despair, Gawain beseeches the Virgin Mary to guide him, and almost immediately stumbles upon the castle of Bertilak. In Fitt III, Gawain draws upon his Christian faith and chivalric loyalty to Bertilak to counter the sexual advances of Lady Bertilak: "And all that passed between them was music and bliss and delight./But the danger might have been great / Had Mary not watched her knight!" (Gardner ll.1766-70) His human sexual desire, coupled with the chivalric sense of duty to a lady, are formidable adversaries to his religious faith and chivalric loyalty to the lord but ultimately, it is his human fear of death that defeats his chivalric values when Gawain decides to keep the green girdle.
This failure is certainly understandable from a human perspective, and the Green Knight pardons Gawain after wounding him in an exchange stroke. But Gawain himself, so tied to a sense of chivalry and morality, dwells upon his moral failing. He at first blames the wily Morgan le Fay and Lady Bertilak in an unexpected misogynistic outburst (ll. 2407-2428), but ultimately can only come to blame himself his cowardice and covetousness -- for his failure. By the end, the experience has shattered Gawain's faith in himself and in a society which cannot see his moral failure. In this way, the poet uses Gawain's character to subtly question the validity of societal and chivalric values, and to question the strength of human nature when compared to the infallibility of Godliness.
The Green Knight
As the other title character, the Green Knight functions mainly as a static foil to the dynamic character of Gawain. We see him in two different guises: first as the Green Knight who bursts into Arthur's court to issue a beheading challenge, and secondly as the generous, noble, though somewhat mischievous lord who hosts Gawain in the days before the New Year. It is not until Fitt IV, after the exchange stroke has been given, that we realize the Green Knight and the lord are one and the same. Thus, the character is shrouded in mystery and we know no more about him than the baffled Gawain does.
As the Green Knight, he represents an Otherworldly, natural force intruding into the refined circle of Camelot. His green color, enormous size, and apparent immortality indicate his Otherworldliness; he seems allied with Nature in all its furious, regenerative grandeur. Many critics here point out out his resemblance to the Green Man of Celtic/English legend, and certainly the Green Knight can be seen as a symbol of the fertility and magnitude of Nature, as opposed to Society. He mocks the reputation of Arthur's court, and in this sense can also be seen in opposition to the artificial constructions of society, its values, and its pretensions. In Fitt IV, he is very much the same figure, superhuman, supercilious, yet respectful of true courage. In this guise, the Green Knight is always a figure of awe and fear, clearly operating above the constructions and restrictions of the human world.
Bertilak de Hautdesert
As Bertilak, the Green Knight is not quite so formidable and easily fits the role of the generous, civilized host who treats Gawain with the respect befitting his reputation. However, he proposes an unusual pact to exchange each day's winnings with Gawain, and seems nonchalantly aware of the attraction between Gawain and his own wife. Again, there is the sense that the lord is operating above and beyond the rules of Gawain's world. This is all quite subtle, though, and is not fully realized until Fitt IV. In the hunting scenes, the vigorous Bertilak seems to function with an innate connection to the natural world, perhaps suggesting his true identity as the primal, visceral Green Knight.
Lady Bertilak
The only other character with a major role, Lady Bertilak's motives seem all too clear until the surprising explanation in Fitt IV that all her advances have been staged. A static character, she serves as a temptation for Gawain to break his chivalric duty to Lord Bertilak and his Christian duty to uphold his moral purity. And yet, she approaches him in such a way that challenges Gawain's chivalric sense of courtly love: would he not be dishonoring a noble lady by rejecting her requests for passion? The dialogue between Gawain and Lady Bertilak in these bedroom scenes is a fascinating study of careful diplomatic arguments around and about the topic of courtly love and chivalry. In a sense, Lady Bertilak triumphs by giving Gawain the green girdle which he does not relinquish to her husband. However, it is his fear of death more than his covetousness or his sense of chivalry that causes him to hide the girdle. And yet, at the end it is revealed that Lord and Lady Bertilak have been conspiring with each other to outwit Gawain in this game. Thus, just as Bertilak pursued beasts relentlessly in the hunting scenes, Lady Bertilak pursued Gawain relentlessly in the bedroom, pushing him to the limit of his moral capacity.
King Arthur
Arthur plays a small role in the poem, functioning primarily as the figurehead of Camelot, the epitome of chivalric society. However, the author does not perhaps portray Arthur in a thoroughly positive light. In Fitt I, the author suggests that the young Arthur, while gentle and noble, may perhaps be too immature in his need for entertaining adventures and marvels. He accepts the Green Knight's challenge only to protect the name of Camelot, when no one else volunteers; he lightly passes over Gawain's new, forbidding mission by turning to revelry at the end of Fitt I; and at the end of the poem he honors Gawain for his bravery without detecting the knight's moral unease. Does Arthur take these matters seriously enough? And if not, what does this say about the validity of his courtly society and its views toward serious moral issues?
Guinevere
Essentially a bit player in the poem, Guinevere, Arthur's queen, functions as the epitome of feminine courtliness. In Fitt I, she is the richly garbed vision of beauty; the author later describes Lady Bertilak as lovelier even than Guinevere to emphasize her entrancing beauty. At the poem's end, she too, is just as unaware as Arthur of Gawain's moral crisis. Perhaps we can see her as a symbol of the superficiality of courtly society.
Old Lady (Morgan le Fay)
A rather strange character, she is the elderly noble lady in Bertilak's castle who befriends Gawain. Hideously ugly, she serves to emphasize Lady Bertilak's beauty while also demonstrating Gawain's virtue and courtesy toward even unattractive ladies. Nevertheless, Bertilak in Fitt IV reveals her to be the scheming Morgan le Fay, Arthur's jealous half-sister and traditional nemesis who engineered the entire beheading game so that Guinevere would be shocked to death. This sort of explanation often comes off as unsatisfactory and artificial to readers, and many view it as a cheap tack-on to an otherwise gripping and emotionally genuine story.
Gawain's Guide
This servant is assigned by Bertilak to guide Gawain to the Green Chapel on New Year's Day. Though he only figures in a few stanzas at the end of Fitt III and the start of Fitt IV, he nevertheless serves two functions: 1) to again emphasize the respect that is shown to the highly-esteemed Gawain, and more importantly, 2) to heighten the sense of fear that the Green Knight incites. His descriptions of the Green Knight are truly terrifying and allow us to feel the fear that Gawain is experiencing and the threat to his mortality.
Gringolet
Gawain's horse, who accompanies him on his journey to face the Green Knight.
Knights of the Round Table
The beginning of the poem describes a Christmas Feast hosted by King Arthur. He is surrounded by his Knights of the Round Table at Camelot, of which Gawain is one.