Wearing a shamrock in the “caubeen” (hat) was a sign of rebellion and green was the colour of the Society of the United Irishmen, a republican revolutionary organisation. During the period, displaying revolutionary insignia was made punishable by hanging.
The Wearing of The Green
by Dion Boucicault (1820-1890)
 O Paddy dear, and did you hear the news that going round?
The shamrock is forbid by law to grow on Irish ground;
St. Patrick’s Day no more we’ll keep, his colours can’t be seen,
For there’s a bloody law against the wearing of the green.
I met with Napper Tandy and he took me by the hand,
And he said, “How’s poor old Ireland, and how does she stand?”
She’s the most distressful counterie that ever yet was seen,
And they’re hanging men and women for the wearing of the green.
Then since the colour we must wear is England’s cruel red,
Sure Ireland’s sons will ne’er forget the blood that they have shed.
You may take a shamrock from your hat and cast it on the sod,
It will take root and flourish there though underfoot it’s trod.
When law can stop the blades of grass from growing as they grow,
And when the leaves in summer-time their verdure dare not show,
Then will I change the colour that I wear in my caubeen
But ’till that day, please God, I’ll stick to wearing of the green.
But if at last our colour should be torn from Ireland’s heart,
Our sons with shame and sorrow from this dear old isle will part;
I’ve heard a whisper of a land that lies beyond the sea
Where rich and poor stand equal in the light of freedom’s day.
O Erin, must we leave you driven by a tyrant’s hand?
Must we ask a mother’s blessing from a strange and distant land?
Where the cruel cross of England shall nevermore be seen,
And where, please God, we’ll live and die still wearing of the green!
