1343 in Ireland

Events from the year 1343 in Ireland.

Incumbent

 * Lord: Edward III

Events

 * May 19 – Robert Savage is appointed Seneschal of Ulster.
 * October 26 – Ferghal mac Diarmata becomes Lord of Moylurg after his brother, Conchobhar Mac Diarmada, dies.
 * Muircheartach Ó Briain, King of Thomond, dies. He is succeeded by his brother, Diarmaid, who is expelled by Brian Bán MacDomnaill Ó Briain.
 * Toirdhealbhach Ó Conchobhair recovers kingship of Connacht from Aodh mac Aodh Breifneach. He makes peace with Mac Diarmada.
 * King Niall Ó Domhnaill of Tir Conaill is deposed by his nephew Aonghus, with the aid and support of O Baoighill, Ó Dochartaigh, the MacSweenys and Aodh Reamhar Ó Neill.
 * Clann Mhuircheartaigh is expelled from Bréifne by Ualgarg Mór Ó Ruairc, O Conchobhair, and Tadhg Mag Ragnaill. He is given refuge by King Aonghus of Tír Conaill in Tír Aodha (Tirhugh, County Donegal).
 * Clanricarde and de Berminghams invade Uí Maine.
 * Maurice Earl of Desmond occupies Imokilly (east County Cork).
 * John L'Archers, Prior of the Order of St. John of Jerusalem appointed Lord Chancellor of Ireland

Deaths

 * October 26 – Conchobhar Mac Diarmada, Lord of Moylurg;
 * Muircheartach Ó Briain, King of Thomond