Fenian

Fenian /ˈfiːnɪən/ was an umbrella term for the Fenian Brotherhood and Irish Republican Brotherhood (IRB), fraternal organisations dedicated to the establishment of an independent Irish Republic in the 19th and early 20th century. The name Fenian was first applied by John O'Mahony to the members of the Irish republican group that he founded in the United States in 1848. O'Mahony, who was a Celtic scholar, named the American wing of the movement after the Fianna. In Gaelic Ireland these were warrior bands of young men who lived apart from society and could be called upon in times of war.

The term Fenian is still used today, especially in Northern Ireland and Scotland, where its original meaning has widened to include all supporters of Irish nationalism. It has also been used as a demeaning term for Irish Catholics and Catholics in general in the British Isles. Irish nationalists, while honouring the 19th century Fenians, more often describe themselves as "nationalist" or "republican".