1870 in Ireland

Events

• 19 May – the Home Government Association is established by Isaac Butt to argue for devolution for Ireland and repeal of the Act of Union.
• 27 August – White Star's first ocean liner RMS Oceanic is launched by Harland and Wolff in Belfast.
• passed in an attempt to secure greater security of tenure for landholders.
• The building of Belfast Castle is completed, to a design by Charles Lanyon and his son.
• Work is completed on the building of the Albert Memorial Clock, Belfast, as a memorial to Queen Victoria's late Prince Consort, Prince Albert.
• First service is held in the new Saint Fin Barre's Cathedral, Cork.
• Belfast Hebrew Congregation is established.

  Arts and literature

• The Water Colour Society of Ireland is founded as the Amateur Drawing Society by an informal group of six well-connected women from County Waterford.

  Sport

Births

• 8 February – Beatrice Grimshaw, anthropologist.
• 8 February – Robert Pilkington, lawyer and politician in the Western Australian Legislative Assembly and House of Commons of the UK.
• 2 April – Edmund Dwyer-Gray, politician and 29th Premier of Tasmania in 1939.
• 17 April – Robert Tressell, born Robert Croker, radical, author of The Ragged-Trousered Philanthropists.
• 5 May – Armar Lowry-Corry, 5th Earl Belmore, High Sheriff and Deputy Lieutenant of County Fermanagh.
• 25 June – Erskine Childers, writer and nationalist.
• 8 July – R. A. Stewart Macalister, archaeologist.
• 16 July – Lambert McKenna, Jesuit priest and writer.
• 16 September – John Boland, Nationalist politician, MP and Olympic tennis gold medallist
• 10 October – Frank Lawless, Sinn Féin TD, member of the 1st Dáil and the 2nd Dáil.
• 19 November – William MacCarthy-Morrogh, cricketer.
• November – Thomas Moles, Ulster Unionist MP.
• Undated – P. T. Daly, trade unionist.

  Deaths

• 17 March – John Keegan Casey, "poet of the Fenians".
• 25 April – Daniel Maclise, painter.
• c. May – John Skipton Mulvany, architect.
• 31 May – Chartres Brew, Gold commissioner, Chief Constable and judge in the Colony of British Columbia.
• 7 September – Hugh Talbot Burgoyne, recipient of the Victoria Cross for gallantry in 1855 in the Sea of Azov, Crimea.
• 23 September – Thomas McCarthy, businessman and politician in Quebec.
• 20 October – Michael William Balfe, composer.
• 9 December – Patrick MacDowell, sculptor.
• 12 December – Martin Cregan, portrait painter.