| 14 May 964 | Italy, Holy Roman Empire [administration] | The deposed pope John XII dies after a stroke, allegedly suffered while in bed with a married woman. He was still only in his mid-twenties. The Romans elect Benedict V the Grammarian as John's successor. |
| 14 May 1027 | France [political events] | In accordance with the custom of the Capetian dynasty, Henry, Duke of Burgundy and eldest son of King Robert II, is crowned as king of France during his father's lifetime. |
| 14 May 1264 | England [political events] | After a failed attempt to make peace, the leader of the baronial opposition to the monarchy, Simon IV de Montfort, Earl of Leicester, defeats and captures King Henry III of England at Lewes, England. |
| 14 May 1509 | France, Venice, Spain, Holy Roman Empire, Italy [wars] | The French under King Louis XII defeat the Venetians at Agnadello. As a result, Pope Julius II annexes Faenza, Rimini, and Ravenna in the Romagna; King Ferdinand II of Aragon takes Otranto and Brindisi; and the Holy Roman Emperor Maximilian I annexes Verona, Vicenza, and Padua. |
| 14 May 1610 | France [political events] | François Ravaillac, a Catholic fanatic in the pay of Jean Louis de la Nogaret de la Valette, Duke of Epernon, assassinates King Henry IV of France, who is succeeded by his nine-year-old son Louis XIII, with Marie de' Medici, the queen mother, as regent. The projected war with the Habsburgs is forgotten. |
| 14 May 1610 | France [births and deaths] | Henry IV, first Bourbon king of France 1589–1610, dies in Paris, France (56). |
| 14 May 1639 | UK [wars] | Royalist and Covenanter forces engage in the Trot of Turriff, a skirmish that opens the First Bishops' War in Scotland. The Covenanter troops are driven out of Aberdeen but retake the city on 19 June 1639. |
| 14 May 1643 | France [births and deaths] | Louis XIII the Just, king of France 1610–43 who together with Cardinal de Richelieu greatly increased his country's political power, dies in Saint-Germain-en-Laye, France (41). |
| 14 May 1727 | England [births and deaths] | Thomas Gainsborough, English portrait and landscape painter, baptized in Sudbury, Suffolk, England (–1788). |
| 14 May 1754 | UK [golf] | The Royal and Ancient Golf Club of St Andrews has its beginnings when 22 ‘Noblemen and Gentlemen’ form themselves into the St Andrews Society of Golfers, at St Andrews, Fife, Scotland. It takes its present name in 1834. |
| 14 May 1907 | Sweden [law and government] | Sweden adopts proportional representation for elections to both chambers of its parliament, and introduces universal adult suffrage for its second chamber. |
| 14 May 1938 | UK, Germany [football] | On the advice of the Football Association and the British Ambassador, the English team give the Nazi salute during the playing of ‘Deutschland über Alles’ before an international football match with Germany in Berlin, Germany. England win the game 6–3. |
| 14 May 1940 | UK [administration] | Recruiting begins for the Local Defence Volunteers (later the Home Guard) in Britain. |
| 14 May 1942 | USA [World War II (1939–45)] | In the USA, women's military involvement in the war begins when Congress founds WAAC (Women's Auxiliary Army Corps). |
| 14 May 1944 | USA [births and deaths] | George Lucas, US film director and producer, born in Modesto, California. |
| 14 May 1955 | USSR, Europe [international organizations] | The Warsaw Treaty (of Friendship, Cooperation, and Mutual Assistance) is signed by the USSR, Albania, Bulgaria, Czechoslovakia, East Germany, Hungary, Poland, and Romania, establishing the ‘Warsaw Pact’ and providing for a unified military command (with headquarters in Moscow) and stationing of Soviet military units in member countries. |
| 14 May 1964 | USSR, Egypt [energy] | The Soviet leader Nikita Khrushchev opens the Aswan Dam in the United Arab Republic (UAR) of Egypt. |
| 14 May 1973–8 February 1974 | USA [space exploration] | The USA launches the Skylab space station. It contains a workshop for carrying out experiments in weightlessness. It is visited by three three-person crews and astronauts make observations of the Sun, manufacture superconductors, and conduct other scientific and medical experiments. The third mission lasts a record 84 days and gathers data about long space flights. |
