St. Patrick’s Day, feast day of St. Patrick, patron saint of Ireland. Many legends grew up around him-for example, that he drove the snakes out of Ireland and used the shamrock to explain the Trinity. Ireland came to celebrate his day with religious services and feasts.
It was emigrants, particularly to the United States, who transformed St. Patrick’s Day into a largely secular holiday of revelry and celebration of things Irish. Cities with large numbers of Irish immigrants, who often wielded political power, staged the most extensive celebrations, which included elaborate parades. Boston held its first St. Patrick’s Day parade in 1737, followed by New York City in 1762. Since 1962 Chicago has colored its river green to mark the holiday. Irish and non-Irish alike commonly participate in the “wearing of the green”—sporting an item of green clothing or a shamrock, the Irish national plant, in the lapel.