In the old Celtic calendar, today is Sheelah’s Day. In ancient Ireland, it was an annual festival to honour the fertility Goddess known as Sheela-na-gig. Naked Sheela-na-gig figures appeared in Irish churches constructed before the 16th century, but most were defaced or destroyed during the prudish Victorian age.

According to some sources, the origins of ‘drowning the shamrock’ have also been traced to this date. In the eighteenth century, William Hone reported on the celebrations surrounding Sheelah, who has been variously identified as the wife, mother, or other relative of St Patrick – noting that, the people of the day ‘are not so anxious to determine who ‘Sheelah’ was, as they are earnest in her celebration. All agree that her immortal memory is to be maintained by potations of whiskey.’ At the end of the day, the faithful would then take their shamrocks and drop them into their respective glasses before downing the contents.