1820 in Ireland

Events from the year 1820 in Ireland.

Events

 * 30 January – Irish-born Royal Navy captain Edward Bransfield in the Williams is the first person positively to identify Antarctica as a land mass.
 * 12 February – the East Indian and Fanny set sail from Cork with settlers for the Cape Colony.
 * 6 May – failure of Newport's Bank in Waterford.
 * 25 May – failure of Roche's Bank and stoppage of Leslie's Bank in Cork.
 * 3 June – the Roman Catholic Cathedral of St Mary and St Anne in Cork is largely destroyed by arson.
 * 8 July – act for lighting the city and suburbs of Dublin with gas.
 * 20 July – Saint Cronan's Boys' National School opens in Bray, County Wicklow, as the Bray Male School.
 * December – Lough Allen Canal, giving through navigation between Carrick-on-Shannon and Lough Allen, opens.
 * The Royal Dublin Society adopts its "Royal" prefix when the new king George IV of the United Kingdom becomes its patron.
 * Suspension of construction of the Wellington Testimonial, Dublin, in Phoenix Park to the design of Robert Smirke.
 * First steamship on the Irish Sea crossing from Dublin to Liverpool, the Waterloo, introduced by George Langtry of Belfast.
 * Frederick Bourne begins to create the village of Ashbourne, County Meath.
 * Publication of James Hardiman's The History of the Town and County of the Town of Galway, from the earliest period to the present time in Dublin.
 * Denny Meats are founded.
 * St. John's Church is built in Ballymore Eustace, County Kildare.

Arts and literature

 * Charles Maturin (anonymously) publishes Melmoth the Wanderer.
 * Regina Maria Roche publishes The Munster Cottage Boy: a Tale.

Births

 * 19 February – John Tuigg, third Roman Catholic Bishop of Pittsburgh, Pennsylvania (died 1889 in the United States).
 * 31 May – Timothy Burns, Lieutenant Governor of Wisconsin from 1851 to 1853 (died 1853).
 * 3 June – Thomas William Moffett, scholar, educationalist and president of Queen's College Galway (died 1908).
 * 4 June – John Kean, businessman and politician in Ontario (died 1892).
 * 2 August – John Tyndall, physicist (died 1893).
 * 6 October – James Travers, soldier, recipient of the Victoria Cross for gallantry in 1857 at Indore, India (died 1884).
 * 22 November – Katherine Plunket, botanical artist and longest-lived Irish person ever (died 1932).
 * 30 December – Mary Anne Sadlier, novelist (died 1903).
 * Full date unknown
 * Thomas Bellew, Galway landowner and politician (died 1863).
 * John F. Kennedy's great-grandfather was born in the village of Dunganstown in County Wexford.
 * Johnston Drummond, early settler of Western Australia, botanical and zoological collector (died 1845).
 * Ambrose Madden, recipient of the Victoria Cross for gallantry in 1854 in the Crimea, at Little Inkerman (died 1863).
 * Patrick Mylott, soldier, recipient of the Victoria Cross for gallantry in 1857 in India (died 1878).
 * Henry Hamilton O'Hara "Mad O'hara", "The Mad Squire of Craigbilly" (died 1875).
 * Kivas Tully, architect (died 1905).

Deaths

 * 29 January – George III of the United Kingdom of Great Britain and Ireland (born 1738).
 * 5 February – William Drennan, physician, poet, educationalist and co-founder of the Society of United Irishmen (born 1754).
 * 13 February – Leonard McNally, informant against members of the Society of United Irishmen (born 1752).
 * 20 March – Eaton Stannard Barrett, poet and author (born 1786).
 * 6 June – Henry Grattan, member of Irish House of Commons and campaigner for legislative freedom for the Irish Parliament (born 1746).
 * Undated – Anthony Daly, a leader of the Whiteboy movement, hanged for attempted murder.