Events from the year 1791 in Ireland.

Incumbent Monarch: George III

Events September – Wolfe Tone publishes Argument on Behalf of the Catholics of Ireland. 14 October – the Northern Whig Club, a group of nine Belfast Presbyterians, meets with Wolfe Tone and Thomas Russell and forms the Society of United Irishmen to press for liberal non-denominational parliamentary reform. 7 November – The Custom House in Dublin opens for business, having been completed under the supervision of James Gandon.

The Grand Canal opens to a junction with the Barrow at Athy. The first bridge across the River Foyle at Derry, built by the American Lemuel Cox in wood, is opened to vehicular traffic.

Births 6 March – John MacHale, Roman Catholic Archbishop of Tuam, Irish Nationalist and writer (died 1881). 17 August – Richard Lalor Sheil, politician, writer and orator (died 1851). 14 December – Charles Wolfe, poet (died 1823). Full date unknown James Graham, soldier, commended for his gallantry during the Battle of Waterloo (died 1845).

Deaths 2 December – Henry Flood, statesman (born 1732). Full date unknown George Bryan, businessman, statesman and politician in Pennsylvania (born 1731). Robert Carver, artist (b. c1730).

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