|Centuries:||18th century – 19th century – 20th century|
|Decades:||1810s 1820s 1830s – 1840s – 1850s 1860s 1870s|
|Years:||1839 1840 1841 – 1842 – 1843 1844 1845|
|1842 in topic:|
|Archaeology – Architecture – Art – Literature – Music|
|Australia – Brazil - Canada – Denmark - France – Germany – Mexico – Norway - Philippines - Portugal– Russia - South Africa – Spain - Sweden - United Kingdom – United States|
|Rail Transport – Science – Sports|
|Lists of leaders|
|Colonial Governors – State leaders|
|Birth and death categories|
|Births – Deaths|
|Establishments and disestablishments categories|
|Establishments – Disestablishments|
|Ab urbe condita||2595|
|British Regnal year||5 Vict. 1 – 6 Vict. 1|
|Chinese calendar||辛丑年 (Metal Ox)
4538 or 4478
— to —
壬寅年 (Water Tiger)
4539 or 4479
|- Vikram Samvat||1898–1899|
|- Shaka Samvat||1764–1765|
|- Kali Yuga||4943–4944|
|Japanese calendar||Tenpō 13
|Julian calendar||Gregorian minus 12 days|
|Minguo calendar||70 before ROC
|Thai solar calendar||2384–2385|
|Wikimedia Commons has media related to 1842.|
1842 (MDCCCXLII) was a common year starting on Saturday (dominical letter B) of the Gregorian calendar and a common year starting on Thursday (dominical letter D) of the Julian calendar, the 1842nd year of the Common Era (CE) and Anno Domini (AD) designations, the 842nd year of the 2nd millennium, the 42nd year of the 19th century, and the 3rd year of the 1840s decade. Note that the Julian day for 1842 is 12 calendar days difference, which continued to be used from 1582 until the complete conversion of the Gregorian calendar was entirely done in 1929.
- January – Michael Alexander takes office as first appointee to the Anglican-German Bishopric in Jerusalem.
- January 6–13 – First Anglo-Afghan War: Massacre of Elphinstone's army (Battle of Gandamak): British East India Company troops destroyed by Afghan forces on the road from Kabul to Jalalabad, Afghanistan, by Akbar Khan, son of Dost Mohammad Khan.
- January 8 – Delft University of Technology established by William II of the Netherlands as a 'Royal Academy for the education of civilian engineers'.
- January 23 – Antarctic explorer James Clark Ross, charting the eastern side of James Ross Island, reaches a Farthest South of 78°09'30"S.
- February 7 – Battle of Debre Tabor: Ras Ali Alula, Regent of the Emperor of Ethiopia, defeats warlord Wube Haile Maryam of Semien.
- March – Commonwealth v. Hunt: the Massachusetts Supreme Court makes strikes and unions legal in the United States.
- March 2 – Gaylad, ridden by Tom Olliver, wins the Grand National at Aintree Racecourse.
- March 5 – Mexican troops led by Rafael Vasquez invade Texas, briefly occupy San Antonio, and then head back to the Rio Grande. This is the first such invasion since the Texas Revolution.
- March 9 – Giuseppe Verdi's third opera Nabucco premieres at La Scala in Milan; its success establishes Verdi as one of Italy's foremost operatic composers.
- March 17 – The Relief Society, a philanthropic and educational women's organization of The Church of Jesus Christ of Latter-day Saints (LDS Church) is founded.
- March 30 – Anesthesia is used for the first time in an operation; Dr. Crawford Long performs the operation using ether.
- March 31 – Middleton Junction and Oldham Branch Railway line opened up to Werneth in North West England.
- April 13 – First Anglo-Afghan War: British victory at the Battle of Jellalabad.
- May 8 – Versailles rail accident: A train traveling between Versailles and Paris in France derails due to a broken locomotive axle and catches fire, killing at least 55 passengers in the locked carriages.
- May 11 – Income Tax Act establishes the first peacetime income tax in the United Kingdom; 7 pence in the pound, for incomes over 150 pounds.
- May 19 – Dorr Rebellion: Militiamen supporting Thomas Wilson Dorr attack the arsenal in Providence, Rhode Island, but are repulsed.
- June 4 – In South Africa, hunter Dick King rides into a British military base in Grahamstown to warn that the Boers have besieged Durban (he had left 11 days earlier). The British army dispatches a relief force.
- June 13 – Queen Victoria becomes the first reigning British monarch to travel by train, on the Great Western Railway between Slough and London Paddington station.
- June 20 – Anselmo de Andrade, Portuguese economist and politician, is born in Vila Real de Santo António.
- June – James Nasmyth patents the steam hammer in the United Kingdom.
- July 8 – A total solar eclipse occurs in Asia.
- July 13 – The Tri-Kap fraternity is founded at Dartmouth College. It is the oldest local fraternity in the United States.
- August 4 – The Armed Occupation Act is signed, providing for the armed occupation and settlement of the unsettled part of the Peninsula of East Florida.
- August 9 – The Webster–Ashburton Treaty is signed, establishing the United States–Canada border east of the Rocky Mountains.
- August 10 – The Mines Act 1842 becomes law, prohibiting underground work for all women and boys under 10 years old in England.
- August 14 – American Indian Wars: United States general William J. Worth declares the Second Seminole War to be over.
- August 29 – The Treaty of Nanking, an unequal treaty between Britain and Qing dynasty China, ends the First Opium War and establishes Hong Kong as a British colony until 1997.
- September – The Treaty of Chushul ends the Sino-Sikh War.
- October 5 – Josef Groll brews the first pilsner beer in the city of Pilsen, Bohemia (now the Czech Republic).
- October 29 – The Iberian Peninsula is struck by a category 2 hurricane.
- November 26 – The University of Notre Dame in South Bend, Indiana (United States) is established by Father Edward Sorin of the Roman Catholic Congregation of Holy Cross.
- December 20 – The Citadel, The Military College of South Carolina, is established.
- Dzogchen Monastery is almost completely destroyed by an earthquake.
- English palaeontologist Richard Owen coins the name Dinosauria, hence the Anglicized dinosaur.
- Julius von Mayer proposes that work and heat are equivalent.
- Pentonville Prison is built in London.
- The New Zealand seat of government moves from Russell to Auckland.
- The Sons of Temperance is founded in New York City.
- Founding of:
- January 11 – William James, American psychologist and philosopher (d. 1910)
- January 15 – Mary MacKillop, first Australian saint (d. 1909)
- February 3 – Sidney Lanier, American writer (d. 1881)
- February 4 – Arrigo Boito, Italian poet and composer (d. 1918)
- February 23 – Karl Robert Eduard von Hartmann, German philosopher (d. 1906)
- February 25 – Karl May, German writer (d. 1912)
- March 2 – Carl Jacobsen, Danish brewer and patron of the arts after whom the Carlsberg brewery was named (d. 1914)
- March 10 – Mykola Lysenko, Ukrainian composer (d. 1912)
- March 18 – Stéphane Mallarmé, French poet (d. 1898)
- March 26 – Alexandre Saint-Yves d'Alveydre, French occultist (d. 1909)
- March 30 – John Fiske, American philosopher (d. 1901)
- April 2 – Dominic Savio, Italian adolescent student of John Bosco (d. 1857)
- May 8 – Emil Christian Hansen, Danish fermentation physiologist (d. 1909)
- May 13 – Arthur Sullivan, English composer (d. 1900)
- June 11 – Carl von Linde, German scientist and engineer (d. 1934)
- June 12 – Rikard Nordraak, Norwegian composer (d. 1866)
- June 24 – Ambrose Bierce, American writer and satirist (d. ca. 1914)
- June 25 – Eloy Alfaro Delgado Gabriel, former President of Ecuador (d. 1912)
- July 4 – Hermann Cohen, German-Jewish philosopher (d. 1918)
- July 30 – Thomas J. O'Brien, American politician and diplomat (d. 1933)
- August 23 – Osborne Reynolds, Irish engineer and physicist (d. 1912)
- September 13 – John H. Bankhead, U.S. Senator (d. 1920)
- September 22 – Abdul Hamid II, Ottoman Sultan (d. 1918)
- October 3 – Frederick Rodgers, American admiral (d. 1917)
- October 14 – Joe Start, baseball player (d. 1927)
- October 28 – Anna Elizabeth Dickinson, American orator (d. 1932)
- November 12
- December 2 – C. W. Alcock, English footballer and football official (d. 1907)
- December 9 – Peter Kropotkin, Russian anarchist (d. 1921)
- December 12
- February 15 – Carlo Andrea Pozzo di Borgo, politician and diplomat (b. 1764)
- March 4 – James Forten, abolitionist.
- March 6 – Constanze Mozart, wife of Wolfgang Amadeus Mozart (b.1762)
- March 13
- March 15 – Luigi Cherubini, Italian composer (b. 1760)
- March 23 – Stendhal, French writer (b. 1783)
- May 8 – Jules Dumont d'Urville, French explorer (b. 1790)
- May 12 – Walenty Wańkowicz, Polish painter (b. 1799)
- July 13 – Prince Ferdinand Philippe, Duke of Orléans, French prince (b. 1810)
- July 25 – Dominique Jean Larrey, French surgeon (b. 1766)
- July 28 – Clemens Brentano, German poet (b. 1778)
- September 10 – William Hobson 1st governor general of nz/ treaty of waitangi writer (b.26 September 1792)
- September 15 – Francisco Morazán, President of Central America (b. 1792)
- October 2 – William Ellery Channing, Influential Unitarian theologian and minister (b. 1780)
- October 20 – Grace Darling, heroine (b. 1815)
- October 24 – Bernardo O'Higgins, first Chilean head of state after independence (b.1778)
- December 1 – Philip Spencer, Founder of Chi Psi Fraternity and midshipman aboard the USS Somers
- December 12 – Robert Haldane, theologian (b. 1764)
- December 24 – Adam Gillies, Lord Gillies, Scottish judge (b. 1760)
- "History of the university". TU Delft. Retrieved 2012-07-10.
- Coleman, E. C. (2006). The Royal Navy in Polar Exploration, from Frobisher to Ross. Stroud: Tempus Publishing. p. 335. ISBN 0-7524-3660-0.
- Palmer, Alan; Veronica (1992). The Chronology of British History. London: Century Ltd. pp. 264–266. ISBN 0-7126-5616-2.
- Green, Oliver (2011). Discovering London Railway Stations. Shire Publications. ISBN 978-0-7478-0806-0.
- Smiles, Samuel (1912). James Nasmyth Engineer: an Autobiography. John Murray. Retrieved 2009-11-14.
- Owen, R. (1842). "Report on British Fossil Reptiles." Part II. Report of the British Association for the Advancement of Science, Plymouth, England.
- von Mayer, J. R. (1842). "Bemerkungen über die Kräfte der unbelebten Nature ("Remarks on the forces of inorganic nature")". Annalen der Chemie und Pharmacie. 43: 233–40. doi:10.1002/jlac.18420420212. Retrieved 2012-01-27.