January 7 – The College of Sorbonne votes a resolution that it is just and necessary to depose King Henry III of France, and that any private citizen is morally free to commit regicide.
February 6 – King Philip of Portugal issues an order to the Viceroy in Portuguese India (Goa) for the arrest of explorer João da Gama, but da Gama continues toward Mexico without being aware of the order.
March 8 – England prohibits the construction of a cottage on any property that isn't at least four acres in size, with the passage of the Erection of Cottages Act 1588.
May 2 – Girolamo Bargagli's play The Pilgrim Woman is given its first performance, premiering in Florence, three years after Bargagli's death.
May 4 – In Spain, María Pita leads the defense of La Coruña against the English Armada after her husband is killed by a crossbow."
May 11 – The Earl of Bothwell, accused of treason against the Crown of Scotland, surrenders along with the Earl of Huntly and is imprisoned at Holyrood Palace. Convicted on May 24, the conspirators are never sentenced and set free by King James VI.
June 28 – On the island of Sumatra in what is now Indonesia, the Sultan of Aceh Darussalam, Ali Ri'ayat Syah II, is assassinated by a group of nobles dissatisfied with his rule. He becomes the fourth Sultan in a row to be murdered. Sayyid al-Mukammal is approved by the nobles as the new Sultan of Aceh.
July–September
July 1 – The English Armada, commanded by Sir Francis Drake, returns to Portsmouth after almost three months of pillaging the Spanish kingdoms.
July 4 – Jeremias II Tranos is appointed as the Patriarch of Constantinople, leader of the Eastern Orthodox Church, by Ottoman Sultan Murad III.
July 23 – Abbas the Great, who has recently become the Safavid Emperor of Persia, arranges the assassination of his benefactor, the Viceroy Murshid Qoli Khan at a banquet.
August 1 – King Henry III of France is assassinated by a fanatical DominicanfriarJacques Clément, who approaches the King on the pretext of delivering a secret message. Henry tells his guards to stand aside, and Clément approaches and fatally stabs the King. Clément is subsequently killed by the guards. King Henry dies the next day.
August 2 – Following the death of Henry III of France, his army is thrown into confusion and an attempt to retake Paris is abandoned. Henry of Navarre succeeds to the throne as King Henry IV of France, but is not recognized by the Catholic League, who acclaim the imprisoned Charles, Cardinal de Bourbon, as the rightful King of France, Charles X.
October 26 – Japanese warlord Date Masamune and his forces capture the Sukagawa Castle, defended by his aunt Onamihime Nikaido, after her assistant Hodohara Yukifuji betrays her.
October 31 – Alleged serial killer and accused werewolf Peter Stumpp 'the Werewolf of Bedburg' is tortured and executed.
