John O'Mahony  John Francis O'Mahony (1815 – 7 February 1877) was a Gaelic scholar and the founding member of the Fenian Brotherhood in the United States, sister organisation to the Irish Republican Brotherhood. O'Mahony was born in 1815 in Kilbeheny, County Limerick or Cork or Tipperary, Ireland, into a family of minor Roman Catholic landed gentry. His father and uncle had been members of the United Irishmen and had taken part in the Irish Rebellion of 1798. He was educated at Midleton College by Dr Hamblin. On the death of an elder brother, O'Mahony inherited a property which yielded £300 per annum. He entered Trinity College, Dublin, where he studied Sanskrit, Hebrew and Irish. He became an accomplished Gaelic scholar, and later taught Greek and Latin, and contributed articles to Irish and French journals. He left Trinity without getting a degree. In 1843, he joined Daniel O'Connell's movement for the Repeal of the Union Act of 1800, but quickly became dissatisfied with the lack of progress and joined "Young Irelander" movement which Smith O'Brien led and took part in the failed Young Irelander Rebellion of 1848. His participation in the rebellion obligated him to leave Ireland, and he settled for a time in Paris, where he lived in great poverty. In 1854, he joined John Mitchel in New York City, and took part in the Emigrant Aid Association, the Emmet Monument Association, and other Irish organisations. In 1857, he published "History of Ireland, by Geoffrey Keating, D. D., translated from the Original Gaelic, and Copiously Annotated" (New York, 1857). Todd, in his preface to the "Wars of the Gaedhill with the Gaell", says, "His translation of Keating is a great improvement upon the ignorant and dishonest one published by Mr. Dermod O'Connor more than a century ago, but has been taken from a very imperfect text, and has evidently been executed, as he himself confesses, in great haste." O'Mahony's notes are copied from O'Donovan's "Four Masters", and it was on this ground that Hodges & Smith procured an injunction against the sale of the book in the United Kingdom. The mental strain to which O'Mahony was subjected in the preparation of this work, which brought him no pecuniary gain, affected his reason, and he was removed by his friends for a short time to a lunatic asylum.