What mythical Irish creature is often associated with St. Patrick's Day?

The leprechaun is the mythical Irish creature most often associated with St. Patrick’s Day.

In Irish folklore, the leprechaun is a solitary fairy or nature spirit traditionally portrayed as a small, bearded shoemaker. Older stories describe leprechauns as clever, solitary beings rather than the cheerful green mascots common in modern holiday decorations.

The familiar image developed through folklore, illustration, tourism, advertising, and popular entertainment. Green clothing, pots of gold, rainbows, and mischievous behaviour became especially prominent in Irish-American celebrations. The 1959 Disney film Darby O’Gill and the Little People also helped popularise a leprechaun king and a more theatrical version of the creature.

Leprechauns are not part of the historical story of Saint Patrick himself. They are linked to the holiday because St. Patrick’s Day celebrations broadened into a display of Irish folklore and identity, especially outside Ireland.