1666 in Ireland

Incumbent

• Monarch: Charles [II of England|Charles II]

Events

• February – William Penn moves from London to Ireland to manage his father's estates. In May, he is involved in suppressing a mutiny in the English garrison at Carrickfergus.
• The Parliament of Ireland meets for the last time until 1692.
• Lord Maurice Roche of Castletownroche in County Cork loses his entire estate to Lieutenant Colonel John Widenham who receives the Castle as a reward for his loyalty to the Crown. The Castle of the Roches is thus renamed "Castle Widenham".

Births

• Approximate date – Richard Pockrich, landowner, military commander and politician

Deaths

• August – Richard Burke, 6th [Earl of Clanricarde], peer.
• December 1 – Sir James Ware, historian, politician and Auditor general for Ireland
• Sir Oliver Óge French, Galway merchant.
• Raymond Caron, O.M.R., Franciscan friar and writer
• Approximate date – Thomas Arthur, physician