4 May 1608: His Holiness Pope Paul V received The Earls of Tyrconell and Tyrone at the Palace of Monte Cavallo after their journey from Ireland.
4 May 1836 - The Ancient Order of Hibernians in America was founded in New York City in order to protect Catholics and their Churches from attack.
4 May 1907 – The Irish International Exhibition was opened at Herbert Park, Ballsbridge by the Lord Lieutenant, the Earl of Aberdeen. The Exhibition closed on 9 November.
4 May 1916 - Edward Daly, Michael O'Hanrahan , William Pearse and Joseph Mary Plunkett were executed by firing squad in Kilmainham Jail.
4/5 May 1941: Belfast experienced a further devastating bombardment at the hands of the Luftwaffe—popularly referred to as the “fire raid”. During the course of 3 hours, roughly 100,000 incendiary bombs were dropped, followed by high explosives, from an estimated 200 aircraft, mainly on the central, northern and eastern portions of the city. Over 200 buildings were ablaze by the time of the “all clear” at 4:25 am. Almost 200 people lost their lives.
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