Written in stanzas of alliterative verse, each concluding with a rhyming bob and wheel, it draws inspiration from Welsh, Irish, and English stories, as well as the French chivalric tradition. This makes it an important exemplar of a chivalric romance, typically featuring a hero on a quest that tests his prowess.
On New Year's Day in Camelot, as King Arthur's court exchanges gifts and awaits the start of the feasting, the king expresses his desire to see or hear of an exciting adventure. Suddenly, a gigantic, entirely green figure rides into the hall on a green horse. He wears no armour but wields an axe in one hand and a holly bough in the other. Refusing to fight anyone present, deeming them too weak, he insists on a friendly Christmas game: someone must strike him once with his axe, with the condition that the Green Knight may return the blow in a year and a day. The splendid axe will belong to whoever accepts this deal.
When it seems no other knight dares to accept the challenge, Arthur himself is prepared to step forward. However, Sir Gawain, the youngest of Arthur's knights and his nephew, requests the honour instead. The giant bends and bares his neck, and Gawain neatly severs his head in one stroke. But astonishingly, the Green Knight neither falls nor falters. Instead, he reaches out, picks up his severed head, remounts, and holds it up to Queen Guinevere while its writhing lips remind Gawain that they must meet again at the Green Chapel. He then rides away. Gawain and Arthur admire the axe, hang it up as a trophy, and encourage Guinevere to view the whole matter lightly.
This story, with its rich tapestry of elements and its exploration of chivalry and honour, continues to captivate readers to this day. It offers a fascinating glimpse into the world of medieval romance and the ideals that knights held dear.