The red-bearded man in the neon green suit guarding a pot of gold is almost entirely a modern invention. Before the 20th century leprechauns wore red, ignored rainbows, and in their first medieval appearance were water-dwelling creatures who tried to drag a king of Ulster into the sea. This deep dive follows the leprechaun from the 8th century tale of Fergus son of Leti, through the solitary fairy taxonomy of William Butler Yeats and David Russell McAnally, to the corporate mascot on cereal boxes and basketball jerseys.

We unpack the contested etymology of the name, including the Latin corpus theory, the 2019 Lupercalia proposal and the folk etymology of half shoe; the county-by-county fashions of the logheryman, lurigadaun, luricawne and cluricaune; and how emigration, anti-Irish stage caricatures and Disney’s Darby O’Gill and the Little People flattened regional folklore into a green stereotype. The episode ends with John A. Costello’s 1963 speech against twee tourism and Paul Krugman’s term leprechaun economics, coined after Ireland reported 26.3 percent GDP growth tied to Apple’s tax restructuring.

• Why the first leprechauns were aquatic hostage takers who granted three wishes to King Fergus
• Yeats and McAnally on solitary fairies versus the dangerous trooping fairies of the mounds
• Red coats, cocked hats and buckle shoes: how outdated English fashion became fairy costume
• The 1959 Disney film that ignored the Irish Folklore Commission’s objections
• Leprechaun economics and the poetic link between hoarded war treasure and offshore tax schemes