1804 in Ireland
Events from the year 1804 in Ireland.
Events
- 14 January – Richard Lovell Edgeworth's semaphore line between Dublin and Galway is operational, but is out of use by the end of the year.
- 11 February – the last armed rebel group of the Society of United Irishmen, led by James Corcoran, is betrayed and killed or captured by yeomen near Enniscorthy.
- 4-5 March – Castle Hill convict rebellion in New South Wales led by Irish convicts in Australia.
- April – first boat passes through the Grand Canal throughout between the River Liffey in Dublin and the River Shannon.
- 14 May – Cork Street [Fever Hospital, Dublin], opens in Cork Street, Dublin.
- First Martello Tower erected in Ireland, at Sutton, Dublin.
Births
- Early February – James Bronterre O'Brien, Chartist leader, reformer and journalist.
- 4 April – Andrew Nicholl, painter.
- 7 April – James Emerson Tennent, politician and traveller.
- 18 November – John George, politician, judge and in 1859 Solicitor-General for Ireland.
- 25 December – Frederic Trench, 2nd Baron Ashtown, peer.
- 26 December – Sir [Joseph Napier, 1st Baronet], Conservative Party MP and Lord Chancellor of Ireland.
- 31 December – Francis Sylvester Mahony, humorist and poet .
Deaths
- February – James Corcoran, rebel leader.
- 27 July – Robert Clements, 1st Earl of Leitrim, politician.