Jack the Giant Killer is the great giant-slaying hero of Cornish folk tradition, a clever farmer's son from near Land's End whose exploits were told and retold until they were gathered into one of the most popular of all English chapbook tales. Set in the legendary reign of King Arthur, the story opens with Jack ridding his own country of the giant Cormoran, who lived on St Michael's Mount and waded ashore to plunder the farmers' cattle. Jack dug a great pit by night, covered it with sticks and straw, lured the giant out at dawn with a blast of his horn, and brought him crashing into the trap, where he despatched him — winning the giant's treasure and a belt embroidered in gold, 'This is the valiant Cornishman who slew the giant Cormoran.'
The story
From that first triumph Jack went on to a whole career of giant-killing across Britain. He outwitted the two-headed Welsh giant Thunderdell, the monstrous Blunderbore who imprisoned him, and others besides, relying always on cunning over brute strength — and acquiring, in the fuller versions, a set of magical aids: a cap of knowledge, a coat of invisibility, shoes of swiftness and a sword of sharpness. Entering the service of King Arthur's court, he cleared the land of its remaining giants and was made a Knight of the Round Table.
The tale's deep roots are unmistakably Cornish — a land that, in legend, swarmed with giants — and folklorists have linked Jack's defeat of Cormoran to the older story of Corineus wrestling the giant Gogmagog. First printed in the early 18th century, 'Jack the Giant Killer' became a staple of nursery story and pantomime, and Jack himself the very type of the small, quick-witted hero who topples the great by his wits.