| 24 May 1013 | Germany, Holy Roman Empire, Poland [treaties] | The Peace of Merseberg is signed. Boleslaw Chrobry (the Brave) of Poland pays homage to King Henry II of Germany and is permitted to retain all his conquests with the exception of Bohemia. He is now free to make war in Russia. |
| 24 May 1086 | Papal States, Italy [administration] | Abbot Desiderius of Monte Cassino is elected, against his will, as Pope Victor III to succeed Gregory VII. Rioting forces him to leave Rome before he can consecrated and he resumes his duties as abbot. |
| 24 May 1328 | Byzantine Empire [administration] | Andronicus II, co-emperor of Byzantium, is forced to abdicate, leaving his grandson Andronicus III as sole Greek emperor. |
| 24 May 1337 | France [Hundred Years War (1337–1453)] | King Philip VI of France announces the confiscation of Gascony as a reaction to the ‘rebellion’ of King Edward III of England. Its seizure begins the Hundred Years' War. |
| 24 May 1543 | Prussia, Poland [births and deaths] | Nicolaus Copernicus, Polish astronomer, who put forward the theory that the Earth revolved about its axis and around the Sun, dies in Frauenberg, East Prussia, now Frombork, Poland (70). |
| 24 May 1667 | France, Spain, Spanish Netherlands [War of Devolution (1667–68)] | After issuing a justificatory essay, King Louis XIV of France makes a call to arms and French troops invade the Spanish Netherlands to begin the War of Devolution. His pretext is that under Brabant law his wife Maria Theresa, as a child of King Philip IV of Spain's first marriage, has a much better claim to Spanish territories in the Netherlands than her half brother King Charles II of Spain. |
| 24 May 1819 | UK, Ireland, India [births and deaths] | Victoria, Queen of the United Kingdom of Great Britain and Ireland 1837–1901, empress of India 1876–1901, born in London, England (–1901). |
| 24 May 1844 | USA [media and communication] | The first public telegraph line is strung 60 km/37 mi between Washington, DC, and Baltimore, Maryland. The first message is transmitted by US artist and inventor Samuel Finley Breese Morse who asks ‘What hath God wrought?’ |
| 24 May 1873 | France [administration] | French president Adolphe Thiers is deposed by the monarchist Asembly, and the antidemocratic candidate Marie-Edme-Patrice-Maurice MacMahon, duc de Magenta, is elected in his place. |
| 24 May 1883 | USA [other structures] | The Brooklyn Bridge over the East River between Brooklyn and Manhattan, New York City, opens. Designed by German-born US engineer Augustus Roebling, and completed by his son Washington Roebling, the suspension bridge is the first to use steel cable wire and is the longest in the world, with a span of 486 m/1595 ft. |
| 24 May 1890 | Africa, Belgium, UK [treaties] | By the Mackinnon Treaty between King Leopold II of Belgium and the British East Africa Company, the latter recognizes Leopold's rights on the west bank of the Upper Nile in return for territory near Lake Tanganyika. |
| 24 May 1923 | Ireland [political events] | The Irish nationalist leader Eamon de Valera calls off the guerrilla war, suspended since 27 April, of the anti-Treaty (Anglo-Irish Treaty) republicans who have been fighting for full independence for Ireland because of high losses of men. |
| 24 May 1941 | USA [births and deaths] | Bob Dylan (Robert Zimmerman), US singer and songwriter, known for his ‘protest songs’ of the 1960s, born in Duluth, Minnesota. |
| 24 May 1984 | Middle East [Iran–Iraq War (1980–88)] | Iranian war planes attack oil tankers off the coast of Saudi Arabia, in an apparent effort to widen the Iran–Iraq war. On 27 May, the USA sends Stinger anti-aircraft missiles to Saudi Arabia in case of Iranian attack. |
| 24 May 1993 | Eritrea, Ethiopia [political events] | Eritrea formally becomes independent from Ethiopia, after a 30-year civil war. |
| 24 May 1995 | England [births and deaths] | Harold Wilson, Labour prime minister of Britain 1964–70, 1974–76, dies in London, England (79). |
