John O’Mahony was bom in 1815 near Mitchelstown, County Cork. After the failure of William Smith O’Brien’s attempted rising in July 1848, O’Mahony led his own insurrection. Afterwards he escaped to France and thence to the United States. In 1858 the Fenian movement was founded with O’Mahony as its elected head centre - an office he held for the period during which it was a force in Irish politics in America. O’Mahony tendered his resignation as Fenian head centre some days before his death in February 1877. O’Mahony is, perhaps, the most surprisingly overlooked figure o f mid/late nineteenth century Irish history. Much has been written o f his contemporaries in the Young Ireland movement such as William Smith O’Brien or John Blake Dillon, while O’Mahony himself has not received much attention. Yet he is arguably the most important of the Young Irelanders, on account of his participation in the 1848 events and as the link between the 1848 rising and the foundation of the Emmet Monument Association and the Fenian movement.