Announcement of the discovery of penicillin by Ayrshire-born Sir Alexander Fleming.
September 30, 1928
Arthur Griffith forms Cumann na nGaedheal, which later becomes Sinn Féin
September 30, 1900
Sir Charles Stanford, composer, is born in Dublin
September 30, 1852
The first recorded meeting of the Presbyterian general synod of Ulster is held at Antrim
September 30, 1691
The English poet Edmund Spenser is appointed Sheriff of Cork
September 30, 1598
A great council meets at Dublin on on this date
September 30, 1430
Revolt of Madog ap Llywelyn, Caernarfon Castle taken by Welsh rebels.
September 30, 1294