| 18 October 1622 | France [treaties] | The Treaty of Montpellier ends the rebellion of the Huguenots (French Protestants). The 1598 Edict of Nantes is confirmed. The French towns of La Rochelle and Montauban are left under Huguenot control, but all political meetings are prohibited. |
| 18 October 1672 | Poland, Ottoman Empire [treaties] | The Treaty of Buczacz is signed between Poland and the Ottoman Turks. Poland cedes Podolia and Kamieniec Podolski (now Kamenets Podolsky, Ukraine) to the Ottoman Empire and promises to pay an annual tribute to the Sultan. The treaty also secures most of the Ukraine to the east of the Dnieper for the Cossack hetman (‘headman’) Peter Doroshenko. However, it is never ratified by the Polish Sejm (parliament). |
| 18 October 1676 | North America [wars] | Nathaniel Bacon, leader of the rebellion in Virginia, dies unexpectedly. His forces surrender to the governor Sir William Berkeley with the promise of amnesty. |
| 18 October 1685 | France, UK, Brandenburg, Holy Roman Empire, Germany, United Netherlands [law and government] | After a period of increasing persecution, King Louis XIV of France issues the Edict of Fontainebleau which revokes the Edict of Nantes of 1598 and makes it illegal to be a Protestant in France. As a result, thousands of Huguenot refugees flee to Britain, the United Netherlands, and Brandenburg. |
| 18 October 1748 | Holy Roman Empire, Prussia, Silesia, Germany [treaties] | By the Peace of Aachen (Aix-la-Chapelle), ending the War of the Austrian Succession, there is a general recognition of Francis I as Holy Roman Emperor and of King Frederick II the Great of Prussia's conquest of Silesia. The Pragmatic Sanction, setting out the legitimacy of Maria Theresa of Austria's succession to the Habsburg domains, is also generally recognized. The French evacuate the Austrian Netherlands, recognize George II as king of Great Britain and Ireland, and transfer the Indian city of Madras (now Chennai) to Britain in exchange for Louisbourg (on Cape Breton Island), Nova Scotia. The Spanish Bourbons achieve the ambitions of their mother Elizabeth Farnese: Don Philip acquires the Italian duchies of Parma, Piacenza, and Guastalla, while King Charles Emmanuel III of Sardinia receives the Upper Novara and Vigevano in Milan. All other conquests are restored. |
| 18 October 1817 | Germany [political events] | At the Wartburg festival in Jena, German students gather to celebrate the anniversaries of the death of the German Protestant reformer Martin Luther and the Battle of Leipzig (the defeat of Napoleon I), demonstrating the growing popularity of nationalism in Germany. |
| 18 October 1865 | England [political events] | Henry Temple, Viscount Palmerston, British statesman, prime minister 1855–58 and 1859–65, a Liberal, dies in Brocket Hall, Hertfordshire, England (80). |
| 18 October 1871 | England [births and deaths] | Charles Babbage, English inventor who designed the first digital computer, dies in London, England (78). |
| 18 October 1878 | Germany [legislation] | An anti-Socialist law in Germany prohibits public meetings, publications, and collections, thus driving socialism underground. |
| 18 October 1912 | Anatolia, Ottoman Empire, Bulgaria, Serbia [Balkan wars (1912–13)] | The Ottoman Empire declares war on Bulgaria and Serbia. |
| 18 October 1912 | Italy, Anatolia, Ottoman Empire [treaties] | Italy and the Ottoman Empire sign a peace treaty at Lausanne, Switzerland, by which Tripoli and Cyrenaica are granted autonomy under Italian suzerainty, and Italy restores the Dodecanese Islands to the Ottoman Empire. |
| 18 October 1922 | UK [television] | The privately owned British Broadcasting Company (BBC) is established.It is nationalized as the British Broadcasting Corporation in 1925. |
| 18 October 1926 | [births and deaths] | Chuck Berry, US singer and guitarist and one of the first rock and roll stars, born in St Louis, Missouri. |
| 18 October 1931 | [births and deaths] | Thomas Alva Edison, prolific US inventor who invented the light bulb, phonograph, and motion picture projector, dies in West Orange, New Jersey (84). |
| 18 October 1963 | UK [administration] | The British prime minister Harold Macmillan resigns for reasons of health, and on 19 October, is succeeded by the Scottish peer the Earl of Home, who later disclaims the peerage, is made a Knight of the Thistle, and becomes Sir Alec Douglas-Home. He is elected a member of the House of Commons, for Kinross, on 8 November. |
| 18 October 1967 | USSR [space exploration] | The Soviet spacecraft Venera 4 (launched 12 June) lands on Venus. The first soft landing on another planet, its instrument-laden capsule transmits information about Venus' atmosphere. |
| 18 October 1981 | Greece [elections] | Andreas Papandreou's Panhellenic Socialist Movement (Pasok) wins the Greek general election and, on October 21, he forms Greece's first Socialist government. |
| 18 October 2006 | USA [business and economics] | The Dow Jones Industrial Average index, measuring the average share price and percentage change of 30 major US industrial companies, breaks briefly through the 12,000-point mark for the first time in its 110-year history. |