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 P ...