Events from the year 1804 in Ireland.
|See also:||1804 in the United Kingdom|
Other events of 1804
List of years in Ireland
- 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.
- Early February – James Bronterre O'Brien, Chartist leader, reformer and journalist (died 1864).
- 4 April – Andrew Nicholl, painter (died 1886).
- 7 April – James Emerson Tennent, politician and traveller (died 1869).
- 18 November – John George, politician, judge and in 1859 Solicitor-General for Ireland (died 1871).
- 25 December – Frederic Trench, 2nd Baron Ashtown, peer (died 1880).
- 26 December – Sir Joseph Napier, 1st Baronet, Conservative Party MP and Lord Chancellor of Ireland (died 1882).
- 31 December – Francis Sylvester Mahony, humorist and poet (a.k.a. Father Prout) (died 1866).
- Kirwan, Adrian James (2017). "R. L. Edgeworth and optical telegraphy in Ireland, c.1790–1805". Proceedings of the Royal Irish Academy. Dublin. 117C: 209–35.
- O'Donnell, Ruan (2000). Aftermath: Post-Rebellion Insurgency in Wicklow, 1799–1803. ISBN 0-7165-2638-7.
- Whitaker, Anne-Maree. "Castle Hill convict rebellion 1804". Dictionary of Sydney. Retrieved 2013-03-03.
- Delany, Ruth (1988). A celebration of 250 years of Ireland's Inland Waterways. Belfast: Appletree Press. p. 87. ISBN 0-86281-200-3.
- "History". Martello Tower Sutton. Archived from the original on February 10, 2010. Retrieved 2012-04-25.