| 1845–1958 | Germany [earth sciences] | German naturalist and explorer Alexander von Humboldt lays the basis of modern geography with the publication of Kosmos/Cosmos, in which he arranges geographic knowledge in a systematic fashion. |
| 1861–1870 | USA, UK, Ireland [statistics and demography] | Emigration to the USA from Britain totals 606,896; from Ireland it is 435,779. |
| 1869–1870 | Vatican [Catholicism] | At the First Vatican council, a council of the Roman Catholic Church convened by Pope Pius IX, liberalism is condemned and the infallibility of the pope is asserted. |
| 1870 | England [Christianity] | The English churchman John Newman publishes The Grammar of Assent, a defence of religious belief. |
| 1870 | Ottoman Empire [archaeology] | German archaeologist Heinrich Schliemann begins archaeological excavations at Hissarlik, in Anatolia (modern Turkey), the site of the ancient city of Troy. |
| 1870 | France [ballet] | The ballet Coppélia, ou La Fille aux yeux d'émail/Coppelia, or the Girl with Enamel Eyes by the French composer (Clément-Philibert-) Léo Delibes is first performed, in Paris, France. The choreography is by the French choreographer Arthur Saint-Léon. |
| 1870 | France [fiction] | The French writer Jules Verne publishes his novel Vingt Mille Lieues sous les mers/Twenty Thousand Leagues Under the Sea. |
| 1870 | USA [fiction] | The US writer Bret Harte publishes The Luck of Roaring Camp and Other Stories, which includes, along with the title story, ‘The Outcasts of Poker Flats’ and ‘Tennessee's Partner’. The stories first appeared in the magazine Overland Monthly. |
| c. 1870 | UK [food and drink] | Fish and chip shops start to become popular in the north of England. |
| 1870 | UK [statistics and demography] | The British newspaper the Daily Telegraph has the largest circulation in the world, with sales in excess of 250,000 copies. |
| 1870 | England [transport] | The English inventor James Starley makes the first ‘pennyfarthing’ bicycle, so named because the difference in size between the wheels resembled the difference between the largest and smallest British coins. |
| 1870 | UK, India [telephone services] | A telegraph link between Britain and India opens. |
| 1870 | England [photography] | The English scientist William Henry Fox Talbot reduces photographic exposure time to one-hundredth of a second, making moving pictures feasible. |
| 1870 | Denmark [consumer products] | The Jürgens Mekaniske Establissement in Copenhagen, Denmark, begins manufacturing the Skrivekugle, the first commercial typewriter. |
| 1870 | Egypt, UK [ships and shipping] | The Suez Canal in Egypt is used by 436,000 tons of shipping; 71% of the traffic is British shipping. |
| 10 January 1870 | USA [companies and organizations] | US industrialist John D Rockefeller founds the Standard Oil Company in Ohio; it quickly comes to dominate the US oil industry. |
| March 1870 | USA [legislation] | The Fifteenth Amendment to the US Constitution, guaranteeing black American voting rights, becomes law. |
| 22 April 1870 | Russia, USSR [births and deaths] | Vladimir Ilyich Lenin, founder of the Russian Communist Party, leader of the Russian Revolution, and head of the Soviet Union 1917–24, born in Simbirsk, Russia (–1924). |
| 12 May 1870 | Canada [political events] | Manitoba is made a Canadian province, which helps to end the Red River Rebellion by mixed-blood rebels over territory. |
| 5 June 1870 | Ottoman Empire [natural disasters] | A fire in Constantinople, in the Ottoman Empire, kills 900 people. |
| 9 June 1870 | England [births and deaths] | Charles Dickens, English novelist of the Victorian era, dies in Gad's Hill, Chatham, Kent, England (58). |
| 13 July 1870 | Prussia, France, Spain [Franco–Prussian War (1870–71)] | A French ultimatum to Prussia not to renew its attempts to put a Hohenzollern ruler on the Spanish throne results in the ‘Ems Telegram’, a conciliatory message from King Wilhelm I of Prussia provocatively rewritten by the Prussian chancellor, Otto von Bismarck, to incite war. |
| 18 July 1870 | Papal States [Catholicism] | The Vatican council issues the ‘Declaration of Papal Infallibility’, declaring that papal pronouncements on spiritual questions are not questionable. |
| 19 July 1870 | France, Prussia [Franco–Prussian War (1870–71)] | France declares war on Prussia following its receipt of the ‘Ems Telegram’ of 13 July. |
| 9 August 1870 | UK [women's rights] | The Married Women's Property Act is passed by the British Parliament, making small but significant concessions to equality in Britain. It recognizes a woman's right to keep any money she earns and some of her own possessions. |
| 2 September 1870 | France, Prussia [Franco–Prussian War (1870–71)] | Emperor Napoleon III of France capitulates to the Prussians at Sedan, France, conceding defeat in the Franco-Prussian War. |
| 4 September 1870 | France [Franco–Prussian War (1870–71)] | The French defeat in the Franco-Prussian War leads to a revolt in Paris, France, against the government of Emperor Napoleon III. A provisional government of national defence is set up to continue the war against Prussia and a republic is proclaimed. |
| 1 October 1870 | UK [postal services] | The British Post Office issues the world's first postcards. |
| 12 October 1870 | USA [births and deaths] | Robert E Lee, Confederate general who commanded the Southern armies during the American Civil War, dies in Lexington, Virginia (63). |
| 5 December 1870 | France [births and deaths] | Alexandre Dumas (père), French novelist best known for The Count of Monte Cristo and The Three Musketeers (both 1844), dies in Puys, France (68). |
