May 17

• 1974 Dublin and Monaghan bombings.
• 1974 The Dublin and Monaghan bombings—the worst single day in the history of the Troubles—saw 26 killed and hundreds injured when three bombs exploded without warning in Dublin. Less than an hour later another no-warning car bomb ripped through Monaghan town centre, killing seven people.
• 17–18/1918 In an effort to discredit the leaders of the anti-conscription campaign in the eyes of the American authorities, 73 prominent Sinn Féiners, including Arthur Griffith, Constance Markievicz and William T. Cosgrave, were arrested in a fictitious ‘German plot’.
• 1599 A detachment of the army of the lord lieutenant, the earl of Essex, was set upon by Owney O’More of Laois near the village of Timahoe. The location became known as ‘the Pass of the Plumes’ on account of the number of plumes from English helmets left on the ground. Some 500 English soldiers were killed
• 1944 The supreme commander of the Allied Expeditionary Force, General Dwight D. Eisenhower, made a two-day visit to Northern Ireland to inspect US troops in preparation for D-Day.
• 1974 Twenty-seven people were killed and hundreds injured when three bombs exploded without warning in Dublin. Less than an hour later a bomb exploded in Monaghan town, killing seven others.