McCabe, William Putnam (c.1776–1821), United Irishman, was youngest of the three sons of Thomas McCabe (qv) of Belfast and his first wife Jean (née Woolsey); the fourth child was a daughter. Thomas McCabe, a watchmaker by trade, was eldest of the four sons (all of whom became watchmakers) of Patrick McCabe, a Lurgan clockmaker; a younger son, James (1748–1811), established a notable line of clockmakers in London.
W. P. McCabe, however, was brought up not to be a watchmaker but to make his living from the textile trade (his father's other interests included part-ownership of a cotton mill). McCabe trained in Belfast, Manchester, and Glasgow. From his father he also imbibed the radical political views that led both of them to be early and ardent members of the Society of United Irishmen. His contacts in the textile trade, and his experience of a variety of provincial locations and accents, were to serve him well when in the mid 1790s he became a roving organiser for the movement. A genius for mimicry and disguise, allied to considerable powers of persuasion, made him a very successful exponent of that role throughout Ireland, especially in effecting the change from more or less open politics to a new military-based system after 1795. A veritable Emerald Pimpernel, he managed on numerous occasions to evade capture or escape from custody in the most extraordinary way by bluff or disguise, at various times appearing as a Scottish pedlar, a clergyman, a military officer, even a king's messenger. Arrested in Dublin in May 1798, just before the outbreak of the rebellion, when in charge of the bodyguards conveying Lord Edward FitzGerald (qv) about the city, McCabe succeeded in convincing his captors – a party of Dumbarton Fencibles, no less – that he was an innocent Scotsman and was released.
He thus played no part in the outbreak of the rebellion, but afterwards appeared among the rebels in Kildare, Cork, and Mayo. In December 1798 he left Dublin en route for London and Paris. Before departing for the Continent he travelled to Scotland, where he appears to have made contact with the United Irish leaders imprisoned in Fort George. Then, travelling to Hamburg on an American passport, he made contact with Pamela FitzGerald (qv), Lord Edward's widow, before eventually arriving in Paris. He became a member of the new United Irish Directory (the leadership of the movement in exile) and undertook a number of dangerous missions on its behalf – dangerous because, as a notorious rebel excluded from the general pardon and still at large, he was liable to be hanged if caught and identified. In Scotland again in 1801, he married – in Glasgow, under the name Lee – Elizabeth McNeil (née Lockhart) a widow, by whom he had one child, a daughter. In 1802 he settled at Rouen, where he established a successful cotton mill with financial backing from his father and the approval of the First Consul, Napoleon Bonaparte. This place became a rendezvous for the Irish exiles arriving in France and there, it is said, he trained some of the people involved in Emmet's (qv) rising in 1803. Recent research has confirmed that in later years McCabe had secret contacts with the British authorities. According to the home office papers of Sir Charles Flint, head of the aliens office in London, McCabe became disillusioned with the French government after Emmet's failure and in 1804 made overtures to Castlereagh (qv) and later to Arthur Wellesley (qv) (Irish chief secretary 1807–9). Through the prime minister's private secretary, William Dacre Adams, he made approaches to Pitt himself. Negotiations led to some relaxation of his banishment so far as England and Scotland were concerned, but Ireland remained prohibited. Hopes of turning him into a double agent were disappointed, however: one frustrated official exclaimed, ‘Catch him, hang him, we can identify him afterwards’.
Undeterred, he went to Ireland again in 1817, accompanied this time by his daughter, and visited Belfast, where he was denounced to the authorities by his stepmother, who wanted to cut him out of his father's estate. He was imprisoned again in Kilmainham, this time for eighteen months, in conditions that weakened his health. A fellow prisoner, Constantine Maguire (qv), felt moved to appeal to William Tennent (qv) for help for McCabe, whose family Tennent knew well. Released at last, McCabe and his daughter made the journey home by way of Scotland, where he was arrested again. When some of his friends applied for his release, on the plea that he only travelled on his own business, the home secretary replied: ‘It might be true that Mr McCabe never went to any part of England or Ireland except upon business of his own; but it was very extraordinary that, in whatever part of the king's dominions his own business brought him, some public disturbance was sure to take place’.
McCabe died in Paris on 6 January 1821 and was buried there in the Vaugirard cemetery. With his tireless energy and his talents for organisation and intrigue, he was undoubtedly one of the most practical and effective of the United Irishmen.