I heard once that the standard modern image of the leprechaun appears pretty recently (19th century, or 18th? I forget) in England, at a time when desperate poverty was driving numerous Irish to emigrate to England. The features of that caricature (stunted growth, exaggerated ears, foolish grin, impulsive behaviour and lack of empathy) are chillingly reminiscent of the stigmata of children afflicted by severe fetal alcohol syndrome.

English cartoonists and public appear to have identified symptoms of alcohol poisoning as a stereotype of Irish in general, just as the American public later identified the various developmental effects of chronic iodine deficiency as the "hillbilly" stereotype.

How old is the legend of leprechauns, anyway?