Editing 1866

{{Use mdy dates|date=March 2011}}
{{Year dab|1866}}
{{Year nav|1866}}
{{C19 year in topic}}
[[File:Custozza1866.jpg|thumb|[[June 20]]: Start of the [[Third Italian War of Independence]]]]
[[File:Schlacht-bei-koeniggraetz-von-georg-bleibtreu.jpg|thumb|[[July 3]]: [[Battle of Königgrätz]]]]{{Year article header|1866}}
{{TOC limit|2}}

== Events ==
=== January–March ===
* [[January 1]]
** [[Fisk University]], a [[Historically black colleges and universities|historically black university]], is established in [[Nashville, Tennessee]].
** The last issue of the [[abolitionist]] magazine ''[[The Liberator (anti-slavery newspaper)|The Liberator]]'' is published.
* [[January 6]] – [[Ottoman Empire|Ottoman]] troops clash with supporters of [[Maronite]] leader [[Youssef Bey Karam]],<ref>{{Cite web|url=https://www.ehdenfamilytree.org/getperson.php?personID=I1&tree=ehden|title=Youssef KARAM, I b. May 1823 d. 7 Apr 1889: Ehden Family Tree}}</ref> at St. Doumit in [[Lebanon]]; the Ottomans are defeated.
* [[January 12]]
** The ''[[Royal Aeronautical Society]]'' is formed as ''The Aeronautical Society of Great Britain'' in [[London]], the world's oldest such society.
** British auxiliary steamer {{SS|London|1864}} sinks in a storm in the [[Bay of Biscay]], on passage from the Thames to Australia, with the loss of 244 people, and only 19 survivors.
* [[January 18]] – [[Wesley College, Melbourne]], is established.
* [[January 26]] – [[Volcanic eruption]] in the [[Santorini caldera]] begins.
* [[February 7]] – [[Battle of Abtao]]: A Spanish naval squadron fights a combined [[Peru]]vian-[[Chile]]an fleet, at the island of Abtao, in the [[Chiloé Archipelago]] of southern [[Chile]].
* [[February 13]] – The first daylight [[bank robbery]] in United States history during peacetime takes place in [[Liberty, Missouri]]. This is considered to be the first robbery committed by [[Jesse James]] and his gang, although James's role is disputed.
* [[February 26]] – The [[Calaveras Skull]] is discovered in [[California]]. Purported to be evidence of humans in North America during the [[Pliocene]] epoch, it turns out to be a [[hoax]].
* [[March 13]] – The [[United States Congress]] overwhelmingly passes the [[Civil Rights Act of 1866]], the first federal legislation to protect the rights of African-Americans; U.S. President [[Andrew Johnson]] vetoes the bill on March 27, and Congress overrides the veto on April 9.<ref>"Civil Rights Act of 1866", in ''Encyclopedia of African American History'', Volume 1, Leslie Alexander, ed. (ABC-CLIO, 2010)  p699.</ref>
* [[March 31]] – A [[total lunar eclipse]] occurs.

=== April–June ===
* [[April 4]] &ndash; [[Alexander II of Russia]] narrowly escapes an assassination attempt in the city of [[St Petersburg]].
* [[April 8]] &ndash; The kingdoms of [[Kingdom of Italy|Italy]] and [[Kingdom of Prussia|Prussia]] form an alliance against the [[Austrian Empire]].
* [[April 10]] &ndash; The [[American Society for the Prevention of Cruelty to Animals]] (ASPCA) is founded in New York City by [[Henry Bergh]].
* [[May 1]]&ndash;[[May 3|3]] &ndash; [[Memphis massacre of 1866|The Memphis massacre]]: a rebellion with a series of violent racial events.
* [[May 2]] &ndash; [[Battle of Callao]]: [[Peru]]vian defenders fight the Spanish fleet.
* [[May 7]] &ndash; Student [[Ferdinand Cohen-Blind]] makes a failed attempt to assassinate [[Otto von Bismarck]] in [[Unter den Linden]] in Berlin.
[[File:ShieldNickel.jpeg|thumb|260px|right| [[May 16]]: U.S. [[nickel (U.S. coin)|nickel]] coin approved.]]
* [[May 10]] &ndash; London bank [[Overend, Gurney and Company]] collapses, precipitating [[Panic of 1866]].
* [[May 16]] &ndash; The [[United States Congress]] approves the minting of a nickel 5-cent coin ([[Nickel (United States coin)|nickel]]), eliminating its predecessor, the [[half dime]].
* [[May 24]] &ndash; [[Battle of Tuyutí]]: 32,000 soldiers of the Triple Alliance defeat 24,000 Paraguayan soldiers few miles north of the [[Paraná, Argentina]], in the [[Paraguayan War]], with 16,000 casualties.
* [[May 26]] &ndash; First production of the [[comic opera]] ''[[Cox and Box]]'' by [[F. C. Burnand]] and [[Arthur Sullivan]] at Moray Lodge, [[Kensington]]
* [[May 30]] &ndash; [[Bedrich Smetana]]'s comic opera ''[[The Bartered Bride]]'' premiered in [[Prague]].<ref>{{cite encyclopedia|author-link=John Tyrrell (musicologist)|last=Tyrrell|first=John|editor-first=Laura|editor-last=Macy|title=''The Bartered Bride'' (''Prodaná nevěsta'')|encyclopedia=[[Grove Music Online]]}} {{Subscription required}}</ref>
* [[June 2]] &ndash; [[Fenian]] forces skirmish with Canadian militia at the battles of [[Battle of Ridgeway|Ridgeway]] and [[Battle of Fort Erie (1866)|Fort Erie]].
* [[June 5]] &ndash; Calculations indicate [[Pluto]] (not known at this time) reaches its only [[apsis|aphelion]] (furthest point from the [[Sun]]) between [[1618]] and August 2113.
* [[June 8]] &ndash; The [[Parliament of Canada]] meets for the first time in [[Ottawa]].
* [[June 11]] &ndash; The [[Agra High Court]] is established (later shifted to the [[Allahabad High Court]]).
* [[June 14]] &ndash; The [[Austro-Prussian War]] ("Seven Weeks War") begins when the Austrians and most of the medium-size German states declare war on Prussia.
* [[June 20]] &ndash; The Kingdom of Italy declares war on Austria.
* [[June 22]] &ndash; In [[Sweden]], the [[Riksdag of the Estates]] votes to replace itself by an elected two-chamber [[Riksdag]].
* [[June 27]]&ndash;[[June 29|29]] &ndash; [[Battle of Langensalza (1866)|Battle of Langensalza]]: The Prussians defeat the [[Kingdom of Hanover|Hanoverian]] army.

=== July–September ===
* [[July 3]] – [[Battle of Königgrätz]]: the [[Prussia]]n army under [[Wilhelm I of Germany|King Wilhelm]] and [[Helmuth von Moltke the Elder|Helmuth von Moltke]] defeats the Austrian army of [[Ludwig von Benedek]], leading to a decisive Prussian victory in the Austro-Prussian War.
* [[July 5]] – [[Princess Helena of the United Kingdom|Princess Helena]], third daughter of [[Queen Victoria]], marries [[Prince Christian of Schleswig-Holstein]].
* [[July 10]] – [[Reconstruction Treaties|Reconstruction Treaty]] with [[Choctaw]] & [[Chickasaw]], [[Timeline of abolition of slavery and serfdom|completing the abolition of slavery]] in the United States; see also [[Choctaw freedmen]].
* [[July 13]] (July 1 [[Old Style]]) – The first Constitution of [[Romania]] is issued.
* [[July 20]] – Austro-Prussian War: Naval [[Battle of Lissa (1866)|Battle of Lissa]] – The Austrian fleet under [[Wilhelm von Tegetthoff]] defeats the Italian fleet of [[Carlo di Persano]].
* [[July 22]] – Austro-Prussian War: [[Battle of Blumenau]] – Austrians defend Bratislava against the Prussian army, concluding the fighting in the war.
* [[July 24]] – [[Reconstruction Era|Reconstruction]]: [[Tennessee]] becomes the first [[U.S. state]] to be readmitted to the [[United States|Union]] following the [[American Civil War]].
* [[July 25]] – The [[United States Congress]] passes legislation authorizing the four-star rank of [[General of the Army (United States)#Post–American Civil War era|General of the Army]] (later reestablished as a five-star rank); Lieutenant General [[Ulysses S. Grant]] becomes the first to have this rank.
[[File:Atlantic cable Map.jpg|thumb|[[July 27]]: [[Atlantic Cable]] completed]]
* [[July 27]] – The {{SS|Great Eastern}} successfully completes laying the [[transatlantic telegraph cable]] between [[Valentia Island]], Ireland, and [[Heart's Content, Newfoundland and Labrador|Heart's Content, Newfoundland]], permanently restoring a communications link.
* [[July 28]] – The ''[[Metric Act of 1866]]'' becomes law and legalizes the standardization of [[weights and measures]] in the United States.
* [[August 23]] – The [[Peace of Prague (1866)|Treaty of Prague]] formally ends the [[Austro-Prussian War]]. The [[Limburg (Netherlands)|Duchy of Limburg]] leaves the [[German Confederation]].
* September – The [[Great Tea Race of 1866]] ends in London, narrowly won by the [[clipper ship]] ''[[Taeping]]''.
* [[September 22]] – [[Paraguay]] successfully [[Battle of Curupayty|defends Curupayty]] against the Triple Alliance in the [[Paraguayan War]], killing more than 5,000 while sustaining just about 50 casualties.

=== October–December ===
[[File:AlfredNobel2.jpg|thumb|[[Alfred Nobel]] invents dynamite in 1866]]
* [[October 12]] – The [[Treaty of Vienna (1866)|Treaty of Vienna]] ends the war between Austria and Italy; it formalizes the annexation of [[Venetia (region)|Venetia]] by Italy.
* [[October 14]] – French troops under the command of Rear Admiral [[Pierre-Gustave Roze]] land at [[Ganghwa Island]], Korea, as part of [[French campaign against Korea (1866)|a punitive expedition against that kingdom]] for the execution of French [[Jesuit]] priests. It is the first military contact between Korea and a Western force.
* [[October 22]] – The office of [[State President of the South African Republic]] is created by constitutional amendment approved at a session of the ''Volksraad''.<ref name="ZAR">[http://www.archontology.org/nations/south_africa/transvaal/00_1857_1877_s.php Archontology.org: A Guide for Study of Historical Offices, South African Republic (Transvaal): Heads of State: 1857–1877] (Accessed on 14 April 2017)</ref>
* [[November 7]] – The Ruse–[[Varna, Bulgaria|Varna]] railway line (the first railway in [[Bulgaria]]) officially opens.
* [[December 12]]– [[Oaks explosion]]: The worst mining disaster in England kills 383 miners and rescuers.
* [[December 18]] – The [[College of Wooster]] is founded in [[Ohio]].<ref>{{cite web|title=Fast Facts|url=http://www.wooster.edu/about/facts|publisher=The College of Wooster|access-date=2013-04-08|archive-date=April 19, 2013|archive-url=https://web.archive.org/web/20130419134824/http://www.wooster.edu/about/facts|url-status=dead}}</ref>

=== Date unknown ===
* [[Federalist]] revolts occur in [[Argentina]].
* [[Alfred Nobel]] invents [[dynamite]] in Germany.
* Foundation of the predecessors of [[Nestlé]] S.A., the Anglo-Swiss Milk Company and Farine Lactée Henri Nestlé.
* The Minneapolis Milling Company, predecessor of [[General Mills]], builds its own mills.
* [[Marcus Jastrow]] arrives in the United States to become rabbi of Congregation Rodeph Shalom in [[Philadelphia]].
* The recommendations of the state [[Girls' School Committee of 1866]] result in a series of progressive reforms in women's rights in Sweden.
* The [[Famine of 1866–68]] begins in Finland.
* Erasmus Jacobs discovers the {{convert|21.25|carat|g|adj=on}} [[Eureka Diamond]] near [[Hopetown]] on the banks of the [[Orange River]] in the [[Cape of Good Hope]].
* [[Magirus|Magirus Kommamditist]], as predecessor of a major worldwide [[Vehicle|commercial vehicles manufacturing brand]], [[Iveco]], is founded in [[Baden-Württemberg]], [[Germany]].{{citation needed|date=September 2021}}

== Births ==

=== January–March ===
[[File:Frank Tudor.jpg|thumb|110px|[[Frank Tudor]]]]
[[File:Emilia Broomé.jpg|thumb|110px|[[Emilia Broomé]]]]
[[File:Matthew Charlton 1925.jpg|thumb|110px|[[Matthew Charlton]]]]
[[File:Reijiro Wakatsuki posing cropped.jpg|thumb|110px|[[Wakatsuki Reijirō]]]]
* [[January 10]] – [[Hermanus Johannes Lovink]], Dutch agriculturalist and politician (d. [[1938]])<ref>{{cite web
 |publisher=[[Huygens Institute for the History of the Netherlands]]
 |url=https://resources.huygens.knaw.nl/bwn1880-2000/lemmata/bwn2/lovink
 |access-date = 8 June 2024
|archive-url=https://web.archive.org/web/20240608002338/https://resources.huygens.knaw.nl/bwn1880-2000/lemmata/bwn2/lovink
 |archive-date=8 June 2024
|last=Poel
 |first=JMG van der
 |title=Lovink, Hermanus Johannes (1866–1938)
 |language=Dutch
 |date=12 November 2013
}}</ref>
* [[January 13]]
** [[George Gurdjieff]], Russian spiritual teacher (d. [[1949]])
** [[Vasily Kalinnikov]], Russian composer (d. [[1901]])
* [[January 15]]
** [[Nathan Söderblom]], Swedish archbishop, recipient of the [[Nobel Peace Prize]] (d. [[1931]])
** [[Horatio Dresser]], American [[New Thought]] religious leader and writer (d. [[1954]])
* [[January 16]] – [[Percy Pilcher]], English inventor and pioneer aviator (d. [[1899]])
* [[January 19]] – [[Harry Davenport (actor)|Harry Davenport]], American actor (d. [[1949]])
* [[January 29]] 
** [[Romain Rolland]], French writer, [[Nobel Prize in Literature|Nobel Prize]] laureate (d. [[1944]])
** [[Frank Tudor]], Australian politician (d. [[1922]])
* [[February 1]] – [[Agda Meyerson]], Swedish nurse and healthcare profession activist (d. [[1924]])
* [[February 2]] – [[Enrique Simonet]], Spanish painter (d. [[1927]])
* [[February 9]] – [[George Ade]], American writer, newspaper columnist and playwright (d. [[1944]])
* [[February 18]] – [[Janko Vukotić]], Montenegrin general (d. [[1927]])
* [[February 26]] – [[Herbert Henry Dow]], Canadian chemical industrialist (d. [[1930]])
* [[March 5]] – [[Arthur Leopold Busch]], English-born American submarine pioneer (d. [[1956]])
* [[March 7]] – [[Hans Fruhstorfer]], German lepidopterist (d. [[1922]])
* [[March 13]] – [[Friedrich Boedicker]], German admiral (d. [[1944]])
* [[March 15]] – [[Matthew Charlton]], Australian politician (d. [[1948]])
* [[March 19]] – [[Emilio De Bono]], Italian general and fascist activist (d. [[1944]])
* [[March 21]]
** [[James Harbord]], American general (d. [[1947]])
** [[Wakatsuki Reijirō]], 25th and 28th [[Prime Minister of Japan]] (d. [[1949]])

=== April–June ===
[[File:Butch Cassidy with bowler hat.jpg|thumb|110px|[[Butch Cassidy]]]]
[[File:AnneSullivanMacy.jpg|thumb|110px|[[Anne Sullivan]]]]
* [[April 1]] – [[Ferruccio Busoni]], Italian pianist and composer (d. [[1924]])
* [[April 3]] – [[J. B. M. Hertzog]], Boer General and 3rd Prime Minister of South Africa (d. [[1942]])
* [[April 8]] – [[Alfred Allen (actor)|Alfred Allen]], American actor (d. [[1947]])
* [[April 13]] – [[Butch Cassidy]], American outlaw (k. [[1908]])
* [[April 14]] – [[Anne Sullivan]], American tutor of [[Helen Keller]] (d. [[1936]])
* [[April 17]] – [[Ernest Starling]], English physiologist (d. [[1927]])
* [[April 18]] – [[Yamaya Tanin]], Japanese admiral (d. [[1940]])
* [[April 21]] – [[Josefa Toledo de Aguerri]], Nicaraguan pioneer educator (d. [[1962]])
* [[April 22]] – [[Hans von Seeckt]], German general (d. [[1936]])
* [[April 24]] – [[Ishii Kikujirō]], Japanese diplomat (d. [[1945]])
* [[May 10]] – [[Richard H. Jackson]], American four-star admiral (d. [[1971]])
* [[May 17]] – [[Erik Satie]], French composer (d. [[1925]])
* [[May 22]] – [[Charles F. Haanel]], American [[New Thought]] author and businessman (d. [[1949]])
* [[June 4]] – [[Miina Sillanpää]], Finnish politician (d. [[1952]])
* [[June 26]] 
** [[George Herbert, 5th Earl of Carnarvon]], English financier of Egyptian excavations (d. [[1923]])
** [[Josef Swickard]], German actor (d. [[1940]])

=== July–September ===
[[File:H.G. Wells by Beresford.jpg|thumb|right|110px|[[H. G. Wells]]]]
[[File:Toulouse-Lautrec - Moulin Rouge - La Goulue.jpg|thumb|110px|[[La Goulue]]]]
[[File:Thomas_Hunt_Morgan.jpg|thumb|right|110px|[[Thomas Hunt Morgan]]]]
[[File:Vassily-Kandinsky.jpeg|thumb|right|110px|[[Wassily Kandinsky]]]]
* [[July 6]] – [[Charles Mangin]], French general (d. [[1925]])
* [[July 9]] – [[Macklyn Arbuckle]], American actor (d. [[1931]])
* [[July 13]] – [[La Goulue]], French dancer (d. [[1929]])
* [[July 25]] – [[Frederick Blackman]], English plant physiologist (d. 1947)
* [[July 27]] – [[António José de Almeida]], 6th President of Portugal and 64th Prime Minister of Portugal (d. [[1929]])
* [[July 28]] – [[Beatrix Potter]], English children's author (''[[Peter Rabbit]]'' and ''[[The Tale of Jemima Puddle-Duck|Jemima Puddle-Duck]]'') (d. [[1943]])
* [[August 2]] – [[Adrien de Gerlache]], Belgian naval officer and explorer (d. [[1934]])
* [[August 4]] – [[Gheorghe Mărdărescu]], Romanian general and politician (d. [[1938]])
* [[August 6]] – [[Chief Thunderbird]], Native American actor (d. [[1946]])
* [[August 8]] – [[Matthew Henson]], African-American explorer (d. [[1955]])
* [[August 12]] – [[Jacinto Benavente]], Spanish writer, [[Nobel Prize in Literature|Nobel Prize]] laureate (d. [[1954]])
* [[August 14]] – [[Dmitry Merezhkovsky]], Russian novelist, poet and religious thinker (d. [[1941]])
* [[September 1]]
:* [[James J. Corbett]], American boxer (d. [[1933]])<ref>{{cite web |title=James J. Corbett {{!}} American boxer |url=https://www.britannica.com/biography/James-J-Corbett |website=Encyclopedia Britannica |access-date=8 August 2021 |language=en}}</ref>
:* [[Thomas F. Woodlock]], editor of ''[[The Wall Street Journal]]'' and [[Interstate Commerce Commission]] commissioner (d. [[1945]])
* [[September 7]] – [[Tristan Bernard]], French writer (d. [[1947]])
* [[September 10]] – [[Jeppe Aakjær]], Danish poet and novelist (d. [[1930]])
* [[September 16]] – [[Joe Vila]], American sportswriter (d. [[1934]])
* [[September 21]]
** [[Charles Nicolle]], French bacteriologist, recipient of the [[Nobel Prize in Physiology or Medicine]] (d. [[1936]])
** [[H. G. Wells]], English writer (d. [[1946]])
* [[September 22]] – [[Witmer Stone]], American ornithologist and botanist (d. [[1939]])
* [[September 27]] – [[Eurosia Fabris]], Italian Catholic ''Blessed'' (d. [[1932]])
* [[September 25]] – [[Thomas Hunt Morgan]], American geneticist, recipient of the [[Nobel Prize in Physiology or Medicine]] (d. [[1945]])

=== October–December ===
[[File:Sun_Yat_Sen_portrait_2.jpg|thumb|right|110px|[[Sun Yat-sen]]]]
[[File:J. Ramsay MacDonald LCCN2014715885 (cropped).jpg|thumb|right|110px|[[Ramsay MacDonald]]]]
* [[October 6]] 
** [[Reginald Fessenden]], Canadian inventor (d. [[1932]])
** [[Nina Bang]], Danish politician (d. [[1928]])
* [[October 12]] – [[Ramsay MacDonald]], Scottish [[Prime Minister of the United Kingdom]] (d. [[1937]])
* [[October 29]]
** [[Antonio Luna]], Filipino general (d. [[1899]])
** [[Dmitri Parsky]], Russian general (d. [[1921]])
* [[November 3]] – [[Paul Lincke]], German composer (d. [[1946]])
* [[November 11]] – [[Martha Annie Whiteley]], English chemist and mathematician (d. [[1956]])
* [[November 12]] – [[Sun Yat-sen]], Chinese revolutionary (d. [[1925]])
* [[November 16]] – [[Cornelia Sorabji]], Indian-born lawyer (d. [[1954]])
* [[November 28]] 
** [[Sy Sanborn]], American sportswriter (d. [[1934]])
** [[David Warfield]], American stage actor (d. [[1951]])
* [[November 30]]
** [[Robert Broom]], Scottish paleontologist (d. [[1951]])
** [[Andrey Lyapchev]], 22nd Prime Minister of Bulgaria (d. [[1933]])
* [[December 2]] – [[Constantin Cristescu]], Romanian general (d. [[1923]])
* [[December 11]] – [[Ada Baker]], Australian soprano, singing teacher and vaudeville star (d. [[1949]])
* [[December 12]] – [[Alfred Werner]], German chemist, [[Nobel Prize in Chemistry|Nobel Prize]] laureate (d. [[1919]])
* [[December 16]] ([[December 4]] O.S.) – [[Wassily Kandinsky]], Russian-born painter (d. [[1944]])
* [[December 17]] – [[Kazys Grinius]], 5th Prime Minister of Lithuania (d. [[1950]])
* [[December 29]] – [[Marie Cahill]], American singer and actress (d. [[1933]])

=== Date unknown ===
* [[Ilia Solomonovich Abelman]], Russian astronomer (d. [[1898]])<ref>{{Cite Jewish Encyclopedia|title=ABELMAN, ILIA SOLOMONOVICH|url=https://www.jewishencyclopedia.com/articles/231-abelman-ilia-solomonovich|author=[[Herman Rosenthal]]|volume=1|page=52}}</ref>
* [[William M. Dalton]], American Old West outlaw (d. [[1894]])

== Deaths ==

=== January–June ===
* January (date unknown) – [[Thomas Baldwin Marsh]], American religious leader (b. [[1799]])
* [[January 16]] – [[Phineas Quimby]], American physician (b. [[1802]])
* [[January 19]] – [[Harriet Ludlow Clarke]], British artist
* [[January 23]] – [[Thomas Love Peacock]], English satirist (b. [[1785]])
* [[January 31]] – [[Friedrich Rückert]], German poet, translator and professor of Oriental languages (b. [[1788]])
* [[February 25]] – [[Sarah Ann Gill]], Barbadian national heroine (b. [[1795]])
* [[March 4]] – [[Alexander Campbell (clergyman)|Alexander Campbell]], Irish/U.S. founder of the [[Disciples of Christ]] (b. [[1788]])
* [[March 6]] – [[William Whewell]], English scientist, philosopher and historian of science (b. [[1794]])
* [[March 20]] – [[Rikard Nordraak]], Norwegian composer (b. [[1842]])
* [[March 21]] – [[Nadezhda Durova]], first female Russian military officer (b. [[1783]])
* [[March 24]] – [[Maria Amalia of Naples and Sicily]], Queen of France (b. [[1782]])<ref>{{cite web |title=Marie-Amélie de Bourbon {{!}} queen of France {{!}} Britannica |url=https://www.britannica.com/biography/Marie-Amelie-de-Bourbon |website=www.britannica.com |access-date=6 September 2022 |language=en}}</ref>
* [[March 28]] – [[Solomon Foot]], American politician (b. [[1802]])
* [[March 29]] – [[John Keble]], British churchman (b. [[1792]])
* [[April 1]] – [[Elizabeth Jesser Reid]], English social reformer, founder of [[Bedford College (London)|Bedford College]] (b. [[1789]])
* [[April 4]]  – [[William Dick (veterinarian)|William Dick]], founder of [[Royal (Dick) School of Veterinary Studies|Edinburgh Veterinary College]] (b. [[1793]])
* [[April 5]] – [[Thomas Hodgkin]], British physician (b. [[1798]])
* [[April 7]] – [[Johann Sedlatzek]], German flautist (b. [[1789]])
* [[April 12]] – [[Peter Hesketh-Fleetwood]], English Member of Parliament and developer (b. [[1801]])
* [[May 13]] – [[Nikolai Brashman]], Russian mathematician of Czech origin (b. [[1796]])
* [[May 29]] – [[Winfield Scott]], American general and presidential candidate (b. [[1786]])
* [[June 7]] – [[Chief Sealth]], Native American for whom [[Seattle]] is named (b. c. [[1786]])
* [[June 17]] – [[Lewis Cass]], American military officer, politician, and statesman (b. [[1782]])

=== July–December ===
[[File:Georg Friedrich Bernhard Riemann.jpeg|thumb|right|110px|[[Bernhard Riemann]]]]
* [[July 20]] – [[Bernhard Riemann]], German mathematician (b. [[1826]])
* [[July 25]] – [[Floride Calhoun]], Second Lady of the United States (b. 1792)
* [[July 29]] – [[Madame Clicquot Ponsardin]], French champagne producer  (b. [[1777]]) 
* [[August 1]] – John Ross, long-serving principal chief of the [[Cherokee Nation]], of natural causes, in Washington D. C. (born 1790 in Cherokee Nation East).
* [[August 6]] – [[Christian Eric Fahlcrantz]], Swedish writer (b. [[1790]])
* [[August 20]] – [[Maria De Mattias]], Italian Catholic saint (b. [[1805]])
* [[August 29]] – [[Tokugawa Iemochi]], 14th ''[[shōgun]]'' of the [[Tokugawa shogunate]] of Japan (b. [[1846]])
* [[September 4]] – [[Theresa Pulszky]], European author (b. [[1819]])
* [[September 30]] – [[Per Gustaf Svinhufvud af Qvalstad]], Swedo-Finnish treasurer of [[Tavastia (historical province)|Tavastia province]], manor host, and paternal grandfather of President [[P. E. Svinhufvud]] (b. 1804)<ref>[https://suomenpresidentit.fi/svinhufvud/?lang=en PEHR EVIND SVINHUFVUD (1861–1944), 1ST REGENT OF FINLAND (1918), 3RD PRESIDENT OF FINLAND (1931–1937)]</ref>
* [[October 13]] – [[Celadon Leeds Daboll]], American merchant and inventor (b. [[1818]])
* [[October 18]] – [[Manuel Bulnes]], Chilean general and politician, [[President of Chile]] (b. [[1799]])
* [[November 11]] – [[Agustín Jerónimo de Iturbide y Huarte]], Prince Imperial of Mexico (b. [[1807]])
* [[November 14]] – King [[Miguel I of Portugal]] (b. [[1802]])
* [[November 26]] – [[Jean-Jacques Willmar]], Luxembourg politician (b. [[1792]])
* [[December 1]] – [[George Everest]], Welsh geodesist (b. [[1790]])
* [[December 21]] – [[William J. Fetterman]], United States Army officer (b. [[1835]]?)<ref>{{cite journal |url=https://archive.org/details/annalsofwyom63141991wyom/page/42 |title=Price of Arrogance: The Short and Controversial Life of William Judd Fetterman |last=McDermott |first=John D. |journal=Annals of Wyoming by Wyoming State Historical Society |volume=63 |issue=2 |pages=42–53 |date=Spring 1991}}</ref>
* December 21 – [[Mercedes Marín del Solar]], Chilean poet, reform educator (b. [[1804]])
* [[December 25]] – [[Hayrullah Efendi]], Ottoman physician, historian, and official (b. [[1818]])<ref>{{TDV Encyclopedia of Islam|volume=17 |pages=67–75 |last=Akün |first=Ömer Faruk |title=Hayrullah Efendi |url=https://islamansiklopedisi.org.tr/hayrullah-efendi}}</ref>

===Date unknown===
*[[Du Bois Agett]], early settler of Western Australia (b. [[1796]])

== References ==
{{Reflist|30em}}

{{Authority control}}

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