| 15 June 763 BC | Neo-Assyrian Empire [astronomy] | Assyrian archivists record an eclipse of the Sun. This is probably the event described in the Bible, in Amos 8:9. |
| 15 June 923 | France [wars] | The usurping king of France, Robert of Neustria, defeats King Charles III the Simple of France at Soissons, but is himself killed in the battle. Charles is captured and imprisoned by Count Herbert of Vermandois. |
| 15–17 June 1215 | England [political events] | King John of England and his opponents, the barons, meet at Runnymede (now in Surrey) on the River Thames, England, to agree on terms for peace. Three days of negotiations result in the Magna Carta (Great Charter) in which the king agrees to various curtailments of his powers and concedes ‘liberties’ to different classes of his subjects. |
| 15 June 1389 | Serbia, , Ottoman Empire [wars] | Following the death of Murad I, ruler of the Ottoman Turks, while defeating the Serbians at Kosovo, he is succeeded by his son Bayezid I. King Lazar of Serbia is also killed in the battle. In the ensuing disintegration of his dominions Montenegro becomes independent. |
| 15 June 1389 | Ottoman Empire [births and deaths] | Murad I, Ottoman sultan 1360–89, father of Bayezid I, whose reign saw rapid expansion in Anatolia and the Balkans, is killed at the Battle of Kosovo, in Serbia (c. 63). |
| 15 June 1520–3 January 1521 | Papal States, Italy, Holy Roman Empire, Saxony, Germany [political events] | Pope Leo X excommunicates the German church reformer Martin Luther for heresy and dissent by the bulls Exsurge Domine/Rise Up, O Lord (which Luther burns at Wittenberg on 10 December) and Decet. |
| 15–17 June 1567 | Scotland [political events] | The Scottish nobility, outraged by Mary Queen of Scots's marriage to the Earl of Bothwell, who is widely regarded as a murderer and usurper, rises and defeats a loyalist army at Carberry Hill. Mary is taken captive, and imprisoned in Lochleven Castle, Fife, on 17 June. Bothwell escapes to Norway. |
| 15 June 1846 | Papal States [Catholicism] | Cardinal Mastai-Ferretti, at this time regarded as a liberal, is elected Pope Pius IX. |
| 15–16 June 1866 | Prussia, Saxony, Hanover, Germany [Seven Weeks War (1866)] | Prussia invades the German states of Saxony, Hanover, and Hesse, which, as Austria's allies, have opposed Prussia's entry into the Austrian-ruled duchy of Holstein. |
| 15 June 1888 | Germany [political events] | Wilhelm II becomes emperor of Germany on the death of his father, Frederick III. |
| 15–23 June 1918 | Italy, Austria-Hungary [World War I (1914–18)] | In the Battle of the Piave, Italy, Austro-Hungarian troops cross the River Piave to attack the Italian line, but are resisted. |
| 15 June 1924 | USA [motor vehicles] | The Ford Motor Company announces the production of its 10 millionth automobile. |
| 15 June 1932 | Bolivia, Panama [wars] | The Chaco War between Bolivia and Paraguay begins, with Bolivians attacking Paraguayan positions in the disputed border territory of Chaco Boreal. |
| 15–17 June 1940 | USSR, Estonia, Latvia, Lithuania [political events] | The USSR occupies the Baltic states of Estonia, Latvia, and Lithuania, formally incorporating them into the USSR in August. |
| 15 June 1969 | France [administration] | Georges Pompidou is elected president of France and, on 20 June, appoints Jacques Chaban-Delmas as prime minister. |
| 15 June 1977 | Spain [elections] | Prime Minister Adolfo Suárez wins a small majority in Spain's first general election since 1936. |
| 15–18 June 1979 | Austria, USA, USSR [diplomacy] | A summit meeting in Vienna, Austria, between the US and Soviet presidents Jimmy Carter and Leonid Brezhnev ends with the signing of the SALT II treaty limiting nuclear weapons between the two countries. |
| 15 June 1985 | South Africa [political events] | South Africa appoints a multiracial administration for Namibia but retains control of the territory's foreign policy and defence. |