The story of Sir Gawain and the Green Knight takes place in medieval England, around the 14th century. The time period is important because it helps to establish the atmosphere of the story. It’s dark, but also full of magic—not unlike a fairy tale.
Sir Gawain is a knight who belongs to King Arthur’s court at Camelot. The Green Knight comes to Arthur’s court with an axe and presents himself as a challenger to any man in Camelot who can strike him first with his axe without being struck back in return. Sir Gawain accepts the challenge and strikes the Green Knight, who then picks up his own axe and prepares to strike Sir Gawain. However, he stops just before he hits Sir Gawain and tells him that he has passed the test—the Green Knight was actually a lord from a nearby kingdom and all of this was just a test of Sir Gawain’s character!