Cheerful, prank-loving leprechauns are beloved symbols of luck and prosperity in Ireland and for the millions of Americans with Irish roots. But centuries-old legends about the diminutive shoemaking creatures painted them differently, as mischievous and sometimes menacing tricksters.

Irish folklore, rich with medieval accounts of dark fairies and goblins, portrayed the mythical humanoids—always described as no more than two or three feet tall—as were fearful beings. The leprechaun’s image has since evolved, blending ancient Celtic mythology with modern cultural charm.

The fairy-like creatures with red beards and green clothes are known for guarding pots of gold and granting wishes to people who catch them. And they’re so popular that they’ve turned into cereal box icons and highlights of St. Patrick’s Day parades.

Here’s how the image of the leprechaun transformed over the ages.

The word leprechaun comes from the “leipreachán” in Irish and “luchorpán” in Old Irish, meaning “small body” or “lobaircin,” which translates to “small-bodied fellow.” In ancient Celtic mythology, leprechauns hail from the “aos sí,” a supernatural race similar to elves and fairies.

The race’s beings, which include leprechauns, banshees and shape-shifting goblins called pookas, were thought to be descendants of the Tuatha Dée Danann, ancient Irish gods living in an alternate realm, according to Medieval Mosaic II by Lea Tassie and Leanne Taylor.

Early folktales depicted leprechauns as wily, somewhat menacing male cobblers who hid their treasures. They were portrayed as cunning and untrustworthy tricksters who were often mean, delighting in leading people astray, stealing or playing harmful pranks.

Among the earliest leprechaun tales is the medieval 7th- or 8th-century tale, The Adventure of Fergus Son of Leti, which depicts leprechauns as dangerous water sprites who try to drag the mythical King Fergus into the sea to drown him. But the king captures them and forces the creatures to grant him three wishes for their release. 

As Ireland moved into the 19th century, the image of the leprechaun softened, with the newer stories about the creatures changing them into mischievous and enterprising figures who outsmart greedy humans trying to get their gold. 

In the 1887 book Ancient Legends, Mystic Charms and Superstitions of Ireland, Jane Francesca Agnes, Lady Wilde (Oscar Wilde’s mother) describes leprechauns as “merry, industrious, tricksy little sprites.” But she also calls them vengeful and “bitterly malicious if they are offended.” 

D.R. McAnally Jr.'s Irish Wonders, believed to have been written in the late 19th century, describes the leprechaun as being "of low descent, his father being an evil spirit and his mother a degenerate fairy." Its pranks were typically minor household mishaps, such as causing a pot to boil over, drinking all the milk or stealing bacon, McAnally writes. 

Thomas Crofton Croker’s 1825 collection, Fairy Legends and Traditions of the South of Ireland, includes the story of “The Little Shoe,” where a man encounters a “little fellow” cobbling shoes, complete with “his little bit of an apron on him, and his hammer in his hand, and a little red nightcap on his head.” 

The man sneaks up on the leprechaun whistling as he works and demands his purse. But the leprechaun cleverly tricks the man into letting him go and escapes, leaving behind only “the prettiest little shoe.”  

William Butler Yeats’ 1888 Fairy and Folk Tales of Ireland describes leprechauns as “withered, old, and solitary” cobblers known for their practical jokes and hidden gold. 

The leprechaun, Yeats writes, “is seen sitting under a hedge mending a shoe, and one who catches him can make him deliver up his crocks of gold, for he is a miser of great wealth; but if you take your eyes off him the creature vanishes like smoke.”

Between 1845 and 1855, 1.8 million Irish immigrants arrived in America, creating large communities that faced widespread poverty and discrimination. The challenges led Irish Americans to embrace their traditions and folklore, including the leprechaun, which quickly became a Celtic pride symbol.

Americans began to feature the leprechaun in St. Patrick’s Day celebrations and by the early 20th century, leprechauns were associated with all things Irish and good luck, becoming embedded in popular culture. 

Perhaps the most prominent example is Lucky the Leprechaun, who debuted on March 17, 1964 (St. Patrick’s Day) as the mascot of Lucky Charms cereal. 

“‘Tis luck to catch a leprechaun!” an advertisement for the cereal announces. “But nobody can! ‘Course if they did–they’d catch my Lucky Charms!” More recently, building leprechaun traps has become a popular St. Patrick’s Day family craft project.

The playful and whimsical leprechaun image made big-screen appearances in films like 1948’s The Luck of the Irish, Disney’s 1959 Darby O’Gill and the Little People, and the 1968 Fred Astaire musical Finian’s Rainbow. More recently, the Leprechaun horror movie franchise that began in 1993 features a creature who goes on murder sprees after his gold is stolen, reviving the leprechaun's historical menacing portrayal.

In the U.S. world of sports, the University of Notre Dame’s "Fighting Irish" teams adopted the leprechaun as the school’s official mascot in 1965. The Boston Celtics introduced its Lucky the Leprechaun mascot in 1968.

Edward O’Donnell, in 1001 Things Everyone Should Know About Irish American History, points out that the modern leprechaun has strayed far from its original Irish mythological roots and now represents a “loveable, but ultimately contemptible” stereotypical character.

Back in Ireland, belief in leprechauns persists in a tongue-in-cheek manner. In 1958, The New York Times reported that Irish President Eamon de Valera’s government was forced to decide whether to punish some government workers for refusing to fence in land they believed to be a “fairy palace” for “little people” that “must not be desecrated.” 

In the country’s Cooley Mountains, the peak of Slieve Foy was declared a “Designated Area of Protection for Flora, Fauna, Wild Animals and Little People” in 2010 under a European Union directive requiring national governments to delineate biodiverse areas for fauna and flora protection.

The addition of little people to the declaration came after the tale of a leprechaun's suit and bones being found there, according to the Irish Independent. The account inspired the decree and the area's annual Carlingford National Leprechaun Hunt.