|Centuries:||18th century – 19th century – 20th century|
|Decades:||1840s 1850s 1860s – 1870s – 1880s 1890s 1900s|
|Years:||1867 1868 1869 – 1870 – 1871 1872 1873|
Year 1870 (MDCCCLXX) was a common year starting on Saturday (link will display the full calendar) of the Gregorian calendar (or a common year starting on Thursday of the 12-day slower Julian calendar).
Events of 1870
January - March
- January 1
- First edition of The Northern Echo newspaper published.
- Plans for the Brooklyn Bridge are completed.
- January 3 - Construction of the Brooklyn Bridge begins.
- January 6 - The inauguration of the Musikverein (Vienna).
- January 10 - John D. Rockefeller incorporates Standard Oil.
- January 15 - A political cartoon for the first time symbolizes the United States Democratic Party with a donkey ("A Live Jackass Kicking a Dead Lion" by Thomas Nast for Harper's Weekly).
- January 26 - Reconstruction: Virginia rejoins the Union.
- January 27 - First college sorority, Kappa Alpha Theta, is established at DePauw University.
- February - Vrain Denis-Lucas in sentenced for two years in prison for multiple forgery in Paris.
- February 1 - Goodna State School in Goodna, Queensland, Australia is founded.
- February 2 - It is revealed that the famed Cardiff Giant was just carved gypsum and not the petrified remains of a human.
- February 3 - The 15th Amendment to the United States Constitution is passed.
- February 10
- Anaheim, California is incorporated.
- The YWCA is founded in New York City.
- February 12 - Women gain the right to vote in Utah Territory.
- February 23 - Military control of Mississippi ends and it is readmitted to the Union.
- February 25 - Hiram Rhodes Revels, a Republican from Mississippi, is sworn into the United States Senate, becoming the first African American ever to sit in the U.S. Congress.
- February 26 - In New York City, the first pneumatic- subway is opened.
- February 28 - The Bulgarian Exarchate is established by decree of Sultan Abd-ul-Aziz of the Ottoman Empire.
- March 2 - Francisco Solano López' last troops cornered by Triple Alliance troops at Cerro Cora. López refuses to surrender and is killed. Fighting ends in Paraguay - the War of the Triple Alliance is over.
- March 4 - Thomas Scott is executed by Louis Riel's provisional government during the Red River Rebellion in modern day Manitoba Canada.
- March 19 - Ohio Legislature passes the Cannon Act, thereby establishing the Ohio Agriculture and Mechanical College, later The Ohio State University.
- March 24 - Syracuse University is established and officially opens.
- March 30
- The 15th Amendment is entered into the United States Constitution, giving blacks the right to vote.
- Texas is readmitted to the Union following Reconstruction.
- March 31 - Thomas Mundy Peterson the first African-American to vote in an election.
April - June
- May 12 - The Canadian province of Manitoba is created in response to Louis Riel's Red River Rebellion.
- May 14 - First rugby match to be played in New Zealand, between the Nelson Football Club and Nelson College.
- May 24 - The Port Adelaide Football Club play their first match of Australian rules football at Buck's Flat, Glanville, South Australia.
- June 9 - The author and actor Charles Dickens dies after suffering from a stroke. The inscription on his tomb reads: "He was a sympathiser to the poor, the suffering, and the oppressed; and by his death, one of England's greatest writers is lost to the world."
- June 22 - The U.S. Congress creates the Department of Justice.
- June 26
July - September
- July 13 - The Ems Dispatch serves as a reason for a war between Prussia and France.
- July 15 - Reconstruction: Georgia becomes the last former Confederate state to be readmitted to the Union, and the CSA is dissoluted.
- July 16 - Lambert McKenna is born, Irish scholar.
- July 19 - Franco-Prussian War: France declares war on Prussia.
- August 8 - The Republic of Ploieşti, a failed rising against Domnitor Carol of Romania.
- August 24 - The Red River Rebellion ends with the arrival of the Wolseley Expedition and the fleeing of Louis Riel.
- September 2 - Franco-Prussian War: Battle of Sedan - Prussian forces defeat the French armies and take emperor Napoleon III and 100,000 of his soldiers prisoner at Sedan.
- September 4 - Emperor Napoleon III of France is deposed and the Third Republic is declared. Empress Eugenie flees to England with her children.
- September 6 - Louisa Ann Swain of Laramie, Wyoming, becomes the first woman in the United States to cast a vote legally since 1807.
- September 20 - With Bersaglieri soldiers entering Rome at Porta Pia, the unification of Italy is completed. End of the last remnant of the Papal States.
October - December
- October 2 - Referendum in Rome supports joining Italy with 133681 against 1500. Decision is made official
- October 6 - Rome becomes the capital of unified Italy.
- October 8 - Leon Michel Gambetta escapes the besieged Paris in a hot-air balloon.
- November 1 - In the United States, the newly-created Weather Bureau (later renamed the National Weather Service) makes its first official meteorological forecast: "High winds at Chicago and Milwaukee... and along the Lakes".
- November 16 - Spanish Cortes Generales proclaims Amadeo de Saboya as King Amadeus I of Spain.
- December 30 - Assassination of Juan Prim, Prime minister of Spain.
|Ab urbe condita||2623|
|British Regnal year||33 Vict. 1 – 34 Vict. 1|
|Chinese calendar|| 己巳年十一月三十日
— to —庚午年十一月初十日
|- Vikram Samvat||1926–1927|
|- Shaka Samvat||1792–1793|
|- Kali Yuga||4971–4972|
|- Ǹrí Ìgbò||870–871|
|Japanese calendar|| Meiji 3
|Juche calendar||N/A (before 1912)|
|Julian calendar||Gregorian minus 12 days|
|Minguo calendar||42 before ROC
|Thai solar calendar||2413|
January - June
- January 2 - Ernst Barlach, German sculptor, graphic artist, and poet (d. 1938)
- January 6 - Gustav Bauer, Chancellor of Germany (d. 1944)
- January 8 - Miguel Primo de Rivera, dictator of Spain (d. 1930)
- January 11 - Alexander Stirling Calder, American sculptor (d. 1945)
- February 7 - Alfred Adler, Austrian psychologist (d. 1937)
- February 12 - Marie Lloyd, English singer (d. 1922)
- March 4 - Thomas Sturge Moore, English poet, author and artist (d. 1944)
- March 5 - Rosa Luxemburg, Polish-born German political theorist, socialist philosopher, and revolutionary (d. 1919)
- March 5 - Frank Norris, American writer (d. 1902)
- March 13 - Seale Harris, American Physician (d. 1957)
- March 17 - Horace Donisthorpe, English entomologist (d. 1951)
- March 20 - Paul Erich von Lettow-Vorbeck, German general (d. 1964)
- April 1 - Hamaguchi Osachi, 27th Prime Minister of Japan (d. 1931)
- April 4 - George Albert Smith, president of The Church of Jesus Christ of Latter-day Saints (d. 1951)
- April 22 - Vladimir Lenin, Russian revolutionary and first Premier of the Soviet Union (d. 1924)
- April 30 - Franz Lehár, Austrian composer (d. 1948)
- May 9 - Harry Vardon, English Golf Professional (d. 1937)
- May 19 - Albert Fish, American serial killer (d. 1936)
- June 13 - Jules Bordet, Belgian immunologist and microbiologist, recipient of the Nobel Prize in Physiology or Medicine (d. 1961)
July - December
- July 3 - Richard Bedford Bennett, eleventh Prime Minister of Canada (d. 1947)
- July 12 - Louis II of Monaco (d. 1949)
- July 25 - Maxfield Parrish, American illustrator (d. 1966)
- July 29 - George Dixon, Canadian boxer (d. 1909)
- August 3 - Caroline Celestia "Carrie" Ingalls, née Swanzey, Younger sister of author Laura Ingalls Wilder (d. June 2, 1946)
- August 11 - Tom Richardson, English cricketer (d. 1912)
- August 31 - Maria Montessori, Italian educator (d. 1952)
- September 25 - James A. Hawken, Schoolteacher (d. 1964)
- September 26 - King Christian X of Denmark (d. 1947)
- September 30 - Jean Baptiste Perrin, French physicist, Nobel Prize laureate (d. 1942)
- October 10 - Ivan Alekseyevich Bunin, Russian writer, Nobel Prize laureate (d. 1953)
- November 21 - Sigfrid Edström, Swedish sports official (d. 1964)
- November 27 - Juho Kusti Paasikivi, Prime Minister and President of Finland (d. 1956)
- December 5 - Vítězslav Novák, Czech composer (d. 1949)
- December 10 - Mary Bonaparte, pretender to the French imperial throne (d. 1947)
- December 12 - Walter Benona Sharp, American oil pioneer (d. 1912)
- December 18 - Saki, English writer (d. 1916)
January - June
- January 29 - Leopold II, Grand Duke of Tuscany (b. 1797)
- February 7 - Sylvain Salnave a Hatian president (b. 1827)
- February 19 - Nathaniel de Rothschild, French wine grower (b. 1812)
- March 11 - Moshoeshoe I of Lesotho (b. 1786?)
- March 28 - George Henry Thomas, American general (b. 1816)
- May 6 - Sir James Young Simpson, Scottish physician and researcher (b. 1811)
- June 9 - Charles Dickens, British novelist (b. 1812)
- June 24 - Adam Lindsay Gordon, Australian poet (b. 1833)
July - December
- July 20 - Jules Alfred Huot de Goncourt, French writer and publisher (b. 1830)
- September 12 - Fitz Hugh Ludlow, American author and explorer (b. 1836)
- September 23 - Prosper Mérimée, French writer (b. 1803)
- October 12 - Robert E. Lee, American Confederate general (b. 1807)
- November 24 - Comte de Lautreamont, French poet and writer (b. 1846)
- November 28 - Frédéric Bazille, French painter (b. 1841)
- December 5 - Alexandre Dumas, père, French author (b. 1802)
- December 27 - General Prim, Spanish dictator (b. 1814)
- date unknown - Patrick MacDowell, Northern Irish sculptor (b. 1799)