1598 in Ireland

Events

• early June – Nine Years' War: Lord Treasurer Thomas Butler backs the claim of the exiled Tadhg O'Rourke for the kingship of West Breifne, causing King Brian Óg O'Rourke to defect back to the rebels.
• June 7 – Nine Years' War: The temporary ceasefire agreed between the Irish rebel lordships and the English in October 1597 expires.
• August 14 – Nine Years' War: Hugh O'Neill, Earl of Tyrone's victory over an English expeditionary force under Henry Bagenal, at the Battle of the Yellow Ford.
• October – Nine Years' War: Edmund Spenser's castle at Kilcolman, near Doneraile in North Cork, is burned down by O'Neill's native Irish forces. Spenser leaves for London shortly afterwards.

  Births

• Patrick D'Arcy, nationalist who wrote the constitution of Confederate Ireland.

  Deaths

• August 14 – Henry Bagenal, Marshal of Ireland, is killed at Yellow Ford.
• August 14 – Maelmora O'Reilly, pretender to the kingship of East Breifne, is killed at Yellow Ford.