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Events from the year 1940 in Ireland.

Incumbents

  • President: Douglas Hyde
  • Taoiseach: Éamon de Valera (FF)
  • Tánaiste: Seán T. O'Kelly (FF)
  • Minister for Finance: Seán T. O'Kelly (FF)
  • Chief Justice: Timothy Sullivan
  • Dáil: 10th
  • Seanad: 3rd

Events

  • January – The Irish Naval Service acquired the first of its six motor torpedo boats, the M1.
  • 3 January – Tomás Óg Mac Curtain shot and mortally wounded Detective Garda Síochána John Roche in Cork city centre. He had been disarmed by Garda Pat Malone in 1935. He was spared the death penalty in view of his father's history.
  • 17 January – The Enid (Captain Wibe) of neutral Norway sailing from Steinkjer to Dublin, 10 miles north of Shetland, went to assist SS Polzella which had been torpedoed by German submarine U-25 which then shelled and sank Enid.
  • 7 February
  • The hanging in Birmingham of two Irish Republican Army men for their part in the 1939 Coventry bombing, despite appeals by Éamon de Valera for commutation of their sentence, led to widespread public protest and mourning in Ireland.
  • The Munster (Captain R. Paisley) was mined and sunk in the Irish Sea while entering Liverpool.
  • 9 February – The case State (Burke) v. Lennon in the Supreme Court of Ireland, confirmed that internment without trial under the Offences against the State Act 1939 was unconstitutional. The government had to enact the Offences Against the State (Amendment) Act, 1940 to reinstate the provisions.
  • 3 March
  • Flooding of Poulaphouca Reservoir was begun by damming the River Liffey at Poulaphouca as part of the Electricity Supply Board project to build Ireland's second hydroelectricity generating station, together with an improved water supply for Dublin.
  • The British Cato (Captain Richard Martin) sailing from Dublin to Bristol, struck a mine 2½ miles west of Nash Point: 13 died, 2 survived.
  • 9 March – The trawler Leukos was sunk by gunfire from German submarine , northwest of Tory Island – 11 died.
  • April – Two men died on hunger strike for political status in Mountjoy Jail, Dublin.
  • 4 May – Operation Mainau: German agent Hermann Görtz parachuted into Ireland to make contact with the IRA.
  • 24 May – The first secret meeting to formulate 'Plan W' – joint action in the event of a Nazi invasion of Ireland – was held between Irish officials and the British military in London.
  • 27 May
  • The Churchill war ministry in London agreed to seek co-operation from Taoiseach Éamon de Valera and the creation of an All-Ireland Council during "the present emergency" (World WarII).
  • The Uruguay of neutral Argentina, sailing from Rosario to Limerick with 6,000 tons of maize, sank with scuttling charges by German submarine 160 miles from Cape Villano: 15 died, 13 survived.
  • 10 June – The Violando N Goulandris of neutral (at this time) Greece sailing from Santa Fe, Argentina to Waterford with a cargo of wheat was torpedoed by German submarine off Cape Finisterre: 6 died, 22 survived.
  • 12 June – German submarine landed a German spy, Karl Simon, in Dingle. He was promptly arrested and interned for the duration of the war.
  • 19 June – The Dublin Institute for Advanced Studies was established.
  • 23 June – Minister Frank Aiken encouraged everyone to store food and water and to prepare a shelter in case of a direct hit.
  • 2 July – The British-owned , carrying civilian internees and prisoners of war of Italian and German origin from Liverpool to Canada, was torpedoed and sunk by off northwest Ireland with the loss of around 865 lives.
  • 4 July – Taoiseach Éamon de Valera announced that the policy of neutrality adopted the previous September would not be reversed.
  • 7 July – Operation Lobster I: Three German agents were infiltrated into Ireland.
  • 11 July – The Moyalla rescued twenty survivors from the British Athellaird off Cape Clear Island.
  • 15 July
  • The City of Limerick (Captain R. Ferguson) was bombed by aircraft and sank in the Bay of Biscay, 700 miles west of Ushant – two died.
  • 10 August – The British armed merchantman was torpedoed off Malin Head by .
  • 15 August – The Meath (Captain T. MacFariane) was mined and sunk off the South Stack, Holy Island, Anglesey;
  • 27 August – The Lanahrone rescued 18 survivors from the British Goathland off the County Kerry coast.
  • 4 September
  • The Luimneach (Captain E. Jones) was sunk by gunfire from German submarine in the Bay of Biscay.
  • 22 October – The Kerry Head (Captain C. Drummond) was bombed again: all twelve hands were lost, in full view of watchers on Cape Clear Island.
  • 24 November – James Craig, the first Prime Minister of Northern Ireland, died suddenly. He had been the longest continually serving Prime Minister in Europe.
  • 19 December – Lightship tender Isolda (Captain A. Bestic) was sunk by German bombers within sight of Carnsore Point: six were killed, seven wounded.
  • 21 December – The Innisfallen (Captain G. Firth) hit a mine off the Wirral Peninsula near New Brighton, Merseyside while leaving Liverpool and sank; four died.
  • 5 August – George Shiels' play The Rugged Path was premiered at the Abbey Theatre, Dublin.
  • Louis MacNeice's poetry collection The Last Ditch (including "The Coming of War" sequence) was published by Cuala Press in Dublin.