Each year on St. Patrick’s Day, tens of thousands of Americans add green to their outfits, even if they can’t trace their ancestry back to the Emerald Isle. But most of those who wear green probably don’t realize that the color has only a tenuous connection to St. Patrick, and actually originated as a symbol of rebellious Irish nationalism.

Avoiding a Leprechaun's Pinch?

One legend suggests that wearing green on St. Patric’s Day makes the wearer invisible to leprechauns. The tiny red-bearded fairies of Irish folklore supposedly roam around pinching those who’ve chosen clothing of another hue.

But fear of leprechauns as a reason to wear green may be American rather than Irish in origin, explains Elizabeth Stack, a native of Ireland who is now executive director of the American Irish Historical Society in New York.

“No one in Ireland is worried that they will be pinched if they don't wear green,” Stack explains. Moreover, she notes, the mischievous mythical creatures don’t actually have anything to do with the feast day of Ireland’s patron saint, who is credited with spreading Christianity on the island in the Fifth Century, in part by blending its rituals with customs of the ancient Celtic pagan religion.  (March 17 is the day that St. Patrick is believed to have died, somewhere around A.D. 460)

For that matter, green isn’t a color that has much of a connection to St. Patrick, either. “The earliest depictions of St. Patrick show him clothed in blue garments,” Stack says.

English Designated Blue for St. Patrick

But during the centuries that Ireland was ruled by the English, the color blue fell into disfavor among the Irish. Henry VIII, who declared himself king of Ireland in 1541, gave Ireland a coat of arms that depicted a golden harp, a traditional symbol of the nation, on a blue background. In the late 1700s, the association between blue and St. Patrick was further tainted for the Irish when the English king George III created a new order of chivalry, the Order of St. Patrick. “Its official color was a sky blue, known as St. Patrick’s blue,” Stack says.

By then, the ever-rebellious Irish had chosen a different hue to symbolize their country. They seized upon green, the color of the shamrock, which in legend St. Patrick used when he explained Christian beliefs to the Irish.

The custom of wearing green “may have come from the tradition of wearing a piece of shamrock on the day in Ireland,” Stack explains. “The significance of the three-leafed shamrock comes from St. Patrick himself. He used the shamrock to describe the three forms of God—the Father, Son and the Holy Spirit—to convert early Irish people to Christianity.”

Green as Sign of Irish Defiance

In the Great Irish Rebellion of 1641, Irish military leader Owen Roe O’Neill’s sailing vessels flew a flag that depicted an Irish harp on a field of green instead of blue, according to Jerrold Casway’s 1984 biography of O’Neill. Even after that uprising was crushed, Thomas Dineley, an Englishman who traveled through Ireland in 1681, “reported people wearing crosses of green ribbon in their hats on Saint Patrick's Day,” Stack says.

In the late 1700s, the Society of United Irishmen, an underground nationalist group that sought to emulate the American Revolution and overthrow English rule, used the color green as a symbol of their cause. To avoid being spotted by the English, a nationalist revolutionary might wear a subtle hint of green, such as a green feather in his cap, according to Robert Kee’s book The Green Flag: A History of Irish Nationalism.

Though the poorly-armed rebels were crushed by the British, the idea of wearing shamrocks attached to hats and the color green as nationalist symbols persisted, despite English attempts to suppress them. As described in Paul F. State’s book A Brief History of Ireland, “The Wearin’ o’ The Green,” a street ballad written by an anonymous songwriter around 1798, conveyed that rebellious meaning:

When law can stop the blades of grass from growing as they grow;
And when the leaves in summertime their verdure dare not show;
Then I will change the colour that I wear in my caubeen (hat),
But until that day, please God, I’ll stick to wearin’ o’ the green.

As Irish immigrants arrived in the United States and other countries in the 1800s, they took the custom of wearing green with them, and it became a prominent feature of the boisterous St. Patrick’s Day parades staged in many cities. In the U.S., Canada, and Australia, where Irish newcomers were often regarded with suspicion, “St. Patrick's Day often performed the function of declaring, almost belligerently, the presence of the Irish among their host community,” Mike Cronin and Daryl Adair write in their history of holiday, The Wearing of the Green.

By the 1930s, the custom of wearing green on St. Patrick’s Day had become so widespread that even President Franklin D. Roosevelt, who was of Dutch ancestry, joined in. An article published on March 17, 1933 described how FDR teased Sen. F. Ryan Duffy of Wisconsin “when he appeared on St. Patrick’s Day wearing a blue tie and no sign of green.” Roosevelt himself wore a green carnation.

The custom has become so established in the U.S. that, according to the National Retail Federation, 82 percent of those who celebrate St. Patrick’s Day mark the holiday by proudly wearing green. 

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