Why We Wear Green On St. Patrick’s Day (Irishman’s Guide)

Every March 17th, cities around the world turn green in celebration of St. Patrick’s Day—but why is green the chosen colour?

And why do some people wear orange?! While Ireland’s nickname as the Emerald Isle and the shamrock’s deep ties to Irish identity play a role, the association wasn’t always there.

In fact, early depictions of St. Patrick, Ireland’s Patron Saint, showed him wearing blue. Here’s what you need to know!

Why do we wear green on St. Patrick’s Day?

Green became associated with St. Patrick’s Day in the 18th century when Irish nationalists adopted the shamrock as a symbol against British rule. Before this, St. Patrick was traditionally depicted in blue, a colour linked to early Irish sovereignty.

This likely dates back to early Irish mythology when the sovereignty of Ireland – “Flaitheas Éireann” – was typically symbolised by a woman dressed in a blue robe. 

1. The Shamrock and St. Patrick

According to legend, Ireland’s most famous missionary needed a simple way to explain the complex doctrine of the Holy Trinity to the pagan Irish. His prop of choice? The humble shamrock.

Three leaves, three persons of the Trinity—sorted. Whether or not it actually happened, the shamrock became tied to St. Patrick, and over time, anything green started being associated with his feast day.

2. Green Runs Deep in Irish Myth and Folklore

Ireland’s love affair with green predates St. Patrick by centuries. The Lebor Gabála Érenn, an 11th-century book of Irish myths, tells the story of Goídel Glas, a man supposedly bitten by a venomous snake and miraculously saved, leaving him with a permanent green mark.

His descendants, the Gaels, went on to settle in a lush, snake-free land—Ireland. A poetic bit of foreshadowing for St. Patrick, who later became famous for “banishing” Ireland’s snakes (a handy metaphor for stamping out paganism).

3. The Rebels Who Put Green on the Map

For a long time, blue, not green, was actually associated with St. Patrick (just look at the old Order of St. Patrick robes). That all changed in the 17th and 18th centuries, when green became the colour of Irish rebellion.

The Irish Catholic Confederation flew green flags in the 1640s, and the United Irishmen—the lads behind the 1798 Rebellion—adopted green as their revolutionary colour.

Wearing green became a political statement, and the British weren’t fans—hence the famous ballad The Wearing of the Green, which tells of Irishmen being persecuted for their choice of clothing.

4. The “Emerald Isle” Gets Its Signature Look

By the late 18th century, poetry, nationalism, and branding sealed green’s fate. William Drennan, a co-founder of the United Irishmen, wrote a poem in 1795 calling Ireland the “Emerald Isle”, and the nickname stuck.

Fast forward to the 1916 Easter Rising, and green featured prominently on flags flown by the rebels fighting for independence.

When the Irish Free State was founded in 1922, postboxes were repainted green, and passports followed suit in 1924. At that point, green wasn’t just a colour—it was Ireland’s identity.

5. How the Irish Diaspora Made Green Go Global

Green took over St. Patrick’s Day thanks to the Irish diaspora, especially in the US. Irish immigrants celebrated their heritage with massive parades, and by the late 19th century, wearing green on March 17th became a must.

Then came the 20th-century marketing machine, which took things up a notch. Guinness, tourism boards, and cities around the world got in on the act, turning St. Patrick’s Day into an international green-fest. 

What green symbolises

The colour green, along with the harp, the Claddagh and the Shamrock, is one of several notable Irish symbols.

From the jerseys worn by Ireland’s rugby team to the liveries on Aer Lingus’s aircraft, green is now the colour of Ireland and it’s everywhere on St Patrick’s Day! 

And the green you’ll see on March 17th is symbolic of a number of iconic images of Ireland, such as the three-leaved shamrock plant, the idea of Ireland as the ‘Emerald Isle’ and, of course, the green third of the Irish flag.

The pinching tradition

Not wearing green on St. Patrick’s Day comes with a warning – you may get pinched! Now, this is an old St. Patrick’s Day tradition and one that you don’t see practised that often. 

Don’t be surprised if you’ve never heard of it, as it seems to be a ‘tradition’ cooked up in America. In fact, it was over in the States where they came up with the wearing green on St Patrick’s Day thing in the first place! 

Anyway, if you’re not wearing green on St. Patrick’s Day then you may be on the receiving end of a pinch, so the tradition goes (if you spend St. Patrick’s Day in Dublin, don’t expect to see this tradition take place).

Wearing green on St. Patrick’s Day may make you invisible to leprechauns

The idea is that wearing green on St. Patrick’s Day is supposed to make you invisible to leprechauns.

Hence, if you’re not wearing green then they’ll be able to spot you in a crowd and the mischievous little cretins will give you a wee pinch for such a huge sartorial blunder. 

But whether you think they’re a quaint part of Irish folklore or not, at least it’s only one day of the year you’ll need to hear stuff like this! 

Green represents the Catholic side of the Irish flag, and it’s also seen as symbolic of other icons of Ireland, such as the shamrock and the emerald isle.

FAQs

If you fancy learning more about St. Patrick’s Day, here are some guides to hop into:

• St. Patrick’s Day Jokes
• The Best Irish Songs And The Best Irish Films Of All Time
• St. Patrick’s Day In Ireland
• St. Patrick’s Day Cocktails 
• Happy St. Patrick’s Day In Irish
• St. Patrick’s Day Prayers
• Fact’s About St. Patrick’ Day
• Facts About Ireland