1800 (MDCCC) was an exceptional common year starting on Wednesday (see link for calendar).

Events

• World population 1 billion.
• February - Foundation of the Bank of France
• March 14 - Cardinal Barnaba Chiaramonti is elected pope as Pius VII.
• March 21 - Pius VII is ordained.
• April 24 - U.S. Library of Congress founded.
• May 5 - Great Britain passes the Act of Union to join Great Britain and Ireland into the United Kingdom to take effect on 1 January 1801. The act is signed by King George III in August.
• May 15 - Napoleon Bonaparte crosses the Alps and invades Italy.
• June 14 - Battle of Marengo, Napoleon defeats the Austrian troops near Marengo, Italy.
• June 2 - First smallpox vaccination in North America, at Trinity, Newfoundland.
• June 27 - Pascha Jussuf Karamanli of Tripoli declares war on Sweden by having the flagpole on the consulate chopped down.
• September 5 - The island of Malta, that was occupied by the French, is conquered by British troops.
• November 1 - U.S. President John Adams becomes the first President of the United States to live in the Executive Mansion (later renamed the White House).
• November 17 - The U.S. Congress holds its first Washington, D.C. session.
• December 3 - Battle of Hohenlinden, the French army defeats the Austrian troops.
• December 24 - An assault on Napoleon Bonaparte fails in Paris.
• December 24 - Pierre Coudrin and Henriette Aymer de la Chevalerie found the Congregation of the Sacred Hearts of Jesus and Mary in Paris.
• Invention of the voltaic pile by Alessandro Volta: the first chemical battery
• The infrared radiation is discovered by Wilhelm Herschel.
• The Althing of Iceland, the world's oldest parliament, is abolished.

Ongoing events

• French Revolutionary Wars (1792-1802)-Second Coalition/Egyptian Campaign
• Napoleonic Wars (1799-1815)-Second Coalition/Egyptian Campaign

Birth

January-April

• January 1 - Francis Egerton, 1st Earl of Ellesmere (died 1857)
• January 7 - Millard Fillmore, 13th President of the United States (died 1874)
• January 11 - Anyos Jedlik, Hungarian physicist, the inventor of the Dynamo (1895)
• January 12 - George Villiers, 4th Earl of Clarendon, English diplomat and statesman (died 1870)
• January 14 - Ludwig von Köchel, Austrian musicologist (died 1877)
• January 17 - Caleb Cushing, American statesman and diplomat (died 1879)
• January 18 - Freeman Towns, American Entrepreneur (died 1862).
• January 24 - Edwin Chadwick, English social reformer (died 1890)
• January 26 - Elizabeth Ann Whitney, Mormon leader (died 1882)
• February 1 - Brian Houghton Hodgson, English civil servant (died 1894)
• February 6 - Achille Devéria, French painter and lithographer (died 1857)
• February 9 - Hyrum Smith, American religious leader (died 1844)
• February 9 - Joseph von Führich, Austrian painter (died 1876)
• February 11 - William Fox Talbot, English photographic pioneer (died 1877)
• February 12 - John Edward Gray, British zoologist (died 1875)
• February 23 - William Jardine, Scottish naturalist (died 1874)
• February 26 - Lucius Lyon, U.S. statesman (died 1851)
• March 2 - Evgeny Baratynsky, Russian poet (died 1844)
• March 3 - Heinrich Georg Bronn, German geologist and paleontologist (died 1862)
• March 10 - Victor Aimé Huber, German social reformer (died 1869)
• March 12 - Louis Prosper Gachard, Belgian man of letters (died 1885)
• March 16 - Emperor Ninko of Japan (died 1846)
• March 17 - Rudolf Ewald Stier, German Protestant churchman and mystic (died 1862)
• March 20 - Gottfried Bernhardy, German philologist and literary historian (died 1875)
• March 25 - Alexis Paulin Paris, French scholar and author (died 1881)
• March 25 - Ernst Heinrich Karl von Dechen, German geologist and mineralogist (died 1889)
• March 28 - Johann Georg Wagler, German herpetologist (died 1832)
• April 4 - Tokugawa Nariaki, Japanese daimyo of Mito (died 1860)
• April 15 - James Clark Ross, British naval officer and explorer (died 1862)
• April 16 - Jakob Heine, German orthopaedist (died 1879)
• April 16 - George Bingham, 3rd Earl of Lucan, British soldier (died 1888)
• April 29 - Hiram Cronk, last surviving veteran of the War of 1812 (died 1905)

May-August

• May 5 - Louis Christophe François Hachette, French publisher (died 1864)
• May 8 - Armand Carrel, French writer (died 1836)
• May 9 - John Brown, American abolitionist (died 1859)
• May 9 - Samuel Carter Hall, English journalist (died 1889)
• June 1 - Charles Fremantle, Royal Navy officer (died 1869)
• June 17 - William Parsons, 3rd Earl of Rosse, Irish astronomer (died 1867)
• June 23 - Karol Marcinkowski, Polish physician and social activist (died 1846)
• July 14 - Jean-Baptiste Dumas, French chemist (died 1884)
• July 19 - Juan José Flores, first president of Ecuador (died 1864)
• July 22 - Jakob Lorber, German Christian mystic (died 1864)
• July 22 - Robert McCormick, British Royal Navy surgeon (died 1890)
• July 31 - Friedrich Wöhler, German chemist (died 1882)
• August 4 - Hercules L. Dousman, American trader and financier (died 1868)
• August 10 - Otto August Rosenberger, German astronomer (died 1890)
• August 12 - Jean-Jacques Ampère, French philologist (died 1864)
• August 19 - Buckner Stith Morris, mayor of Chicago (died 1879)
• August 19 - James Lenox, American bibliophile and philanthropist (died 1880)
• August 22 - Edward Barron Chandler, American politician (died 1880)
• August 22 - William S. Harney, U.S. general (died 1889)
• August 22 - Edward Bouverie Pusey, English churchman (died 1882)
• August 25 - Karl Hase, German Protestant theologian and Church historian (died 1890)

September-December

• September 6 - Catharine Beecher, American educator (died 1878)
• September 11 - Daniel S. Dickinson, Confederate admiral (died 1866)
• September 13 - Franklin Buchanan, officer in the U.S. Navy who became an admiral in the Confederate Navy during the American Civil War (died 1874)
• September 13 - David Stewart, American politician (died 1858)
• September 15 - Paul Friedrich, Grand Duke of Mecklenburg-Schwerin (died 1842)
• September 19 - William McKean, admiral in the United States Navy (died 1865)
• September 20 - Benjamin Franklin White, American singing master (died 1879)
• September 22 - George Bentham, English botanist (died 1884)
• September 22 - Thomas Holloway, English pharmacist and philanthropist (died 1883)
• September 23 - William Holmes McGuffey, American professor who created the McGuffey Readers (died 1873)
• September 30 - Decimus Burton, prolific English architect and garden designer (died 1881)
• October 1 - Lars Levi Laestadius, Swedish Lutheran pastor of Sami ancestry (died 1861)
• October 2 - Nat Turner, American slave rebel (died 1831)
• October 3 - George Bancroft, American historian and statesman (died 1891)
• October 8 - Jules Desnoyers, French geologist and archaeologist (died 1887)
• October 18 - Henry Taylor, English dramatist (died 1886)
• October 22 - Christian Lassen, German orientalist (died 1876)
• October 23 - Henri Milne-Edwards, French zoologist (died 1885)
• October 25 - Thomas Babington Macaulay, 1st Baron Macaulay, British poet (died 1859)
• October 25 - Jacques Paul Migne, French priest, theologian, and publisher (died 1875)
• October 26 - Helmuth von Moltke the Elder, German field marshal (died 1891)
• October 27 - Benjamin Wade, U.S. lawyer and politician (died 1878)
• November 4 - Edwin Waller, Americian entrepreneur (died 1881)
• November 4 - George Long, English classical scholar (died 1879)
• November 17 - Achille Fould, French financier and politician (died 1867)
• November 18 - John Nelson Darby, British evangelist (died 1882)
• November 22 - Linn Boyd, U.S. politician (died 1859)
• November 27 - Frances Anne Kemble, British actress and author (died 1893)
• December 1 - Mihály Vörösmarty, Hungarian poet (died 1855)
• December 3 - France Prešeren, Slovenian poet (died 1849)
• December 4 - Emil Aarestrup, Danish erotic poet (died 1856)
• December 4 - William Fenwick Williams, British military (died 1883)
• December 5 - Thomas Ford, governor of Illinois (died 1850)
• December 7 - Giuseppe Gené, Italian naturalist and author (died 1847)
• December 25 - John Phillips, English geologist (died 1874)
• December 27 - John Goss, English organist and composer (died 1880)
• December 29 - Charles Goodyear, American rubber magnate (died 1860)

Unknown day

• Aga Khan I, Shah of Persia (died 1881)
• Jewgenij Abramovich Baratynski, Russian poet (died 1844)
• Ugo Bassi, Italian patriot (died 1849)
• James Black, creator of the original Bowie knife (died 1870)
• Elias Boudinot, Cherokee who started and edited the tribe's first newspaper (died 1839)
• John McLeod Campbell, Scottish churchman (died 1872)
• Robert L. Caruthers, Confederate governor of Tennessee (died 1882)
• Martín Perfecto de Cos, Mexican general (died 1854)
• Catherine Crowe, British writer (died 1876)
• John Evelyn Denison, 1st Viscount Ossington, English statesman (died 1875)
• Karl Wilhelm Feuerbach, German geometer (died 1827)
• Charles Auguste Désiré Filon, French historian (died 1875)
• James Glynn, United States Navy officer (died 1871)
• Edwin Guest, English antiquary (died 1880)
• James Henry Hackett, United States actor (died 1871)
• Charles Wood, 1st Viscount Halifax, English statesman (died 1885)
• Anna Maria Hall, Irish writer (died 1889)
• George Hudson, English railway financier (died 1871)
• Frederick Yeates Hurlstone, English painter (died 1869)
• Richard Lawrence, attempted assassin of Andrew Jackson (died 1861)
• Thomas Henry Lister, English novelist (died 1842)
• Ramón María Narváez y Campos, Duke of Valencia, Spanish soldier and statesman (died 1868)
• William Nicholson, officer in the United States Navy (died 1872)
• Johann Gerhard Oncken, German Baptist preacher (died 1884)
• Mustafa Resid Pasha, Turkish statesman and diplomat
• William Cavendish-Scott-Bentinck, 5th Duke of Portland (died 1879)
• Gustaw Potworowski, Polish activist (died 1860)
• William Price, British physician and eccentric (died 1893)
• John Baptist Purcell, U.S. (Irish-born) archbishop (died 1883)
• Ippolito Rosellini, Italian Egyptologist (died 1843)
• Roman Sanguszko, Polish noble (died 1881)
• William Simson, Scottish portrait (died 1847)
• Henrietta Constance Smithson, Irish actress (died 1854)
• Pierre St. Amant, leading French chess master (died 1872)
• Nicholas P. Trist, secretary to Andrew Jackson (died 1874)
• A.W. Volkmann, German physiologist (died 1877)
• Richard Bethell, 1st Baron Westbury, Lord Chancellor of Great Britain (died 1873)
• Jacob Westervelt, American shipbuilder and mayor of New York (died 1856)
• Andrzej Artur Zamoyski, Polish nobleman (died 1874)

Death

January-June

• January 1 - Louis-Jean-Marie Daubenton, French naturalist (born 1716)
• January 6 - William Jones, English divine (born 1726)
• January 9 - Jean Étienne Championnet, French general (born 1762)
• January 13 - Dempsey Burges, Republican U.S. Congressman (born 1751)
• January 20 - Thomas Mifflin, fifth President of the United States in Congress assembled under the Articles of Confederation (born 1744)
• January 22 - George Steevens, English Shakespearean commentator (born 1736)
• January 23 - Edward Rutledge, U.S. statesman (born 1749)
• February 2 - James C. Jarvis, United States Navy officer (born 1787)
• February 23 - Joseph Warton, English academic and literary critic (born 1722)
• March 1 - John Hazelwood, officer in the Continental Navy (born 1726)
• March 14 - Daines Barrington, English naturalist (born 1727)
• March 21 - William Blount, U.S. statesman (born 1749)
• March 29 - Marc René, marquis de Montalembert, French military engineer and writer (born 1714)
• April 25 - Ezekiel Cornell, Continental Congressman from Rhode Island (born 1732)
• April 25 - William Cowper, English poet (born 1731)
• May 4 - Armand, duc d'Aiguillon (born 1750)
• May 7 - Niccola Piccinni, Italian composer (born 1728)
• May 18 - Alexander Suvorov, Count of Rymnik (born 1729)
• June 14 - Louis Charles Antoine Desaix de Veygoux, French military leader (killed in battle) (born 1768)
• June 14 - Jean Baptiste Kléber, French general (assassinated) (born 1753)
• June 20 - Abraham Gotthelf Kästner, German mathematician (born 1719)
• June 30 - Thomas Townshend, 1st Viscount Sydney, British politician (born 1732)

July-December

• July 14 - Lorenzo Mascheroni, Italian mathematician (born 1750)
• July 18 - John Rutledge, governor of South Carolina (born 1739)
• August 31 - John Blair, American politician (born 1732)
• September 26 - William Billings, American choral composer (born 1746)
• September 27 - William Gibbons, American lawyer and revolutionary (born 1726)
• September 29 - Michael Denis, Austrian poet (born 1729)
• October 16 - Benjamin Huntington, American lawyer and politician (born 1736)
• October 28 - Artemas Ward, American Major General in the American Revolutionary War and a Congressman from Massachusetts (born 1727)
• November 5 - Jesse Ramsden, English astronomical instrument maker (born 1735)
• December 7 - Wilhelm von Knyphausen, Hessian Lieutenant-General (born 1716)
• December 17 - William Peery, American farmer and lawyer (born 1743)
• December 27 - Hugh Blair, Scottish Presbyterian preacher and man of letters (born 1718)

Unknown day

• Jean-Baptiste Audebert, French artist and naturalist
• Angelo Maria Bandini, Italian author (born 1726)
• Samuel Barrington, British admiral (born 1729)
• François Claude Amour, marquis de Bouillé, French general (born 1739)
• Thomas Conway, Irish soldier (born 1734)
• Henry Cort, English ironmaster
• George Dixon, English sea captain and explorer (born 1755)
• Joseph de Guignes, French orientalist (born 1721)
• Johann Hermann, German physician and naturalist (born 1738)
• Charles Johnstone, Irish writer (born 1719)
• Rawlins Lowndes, American lawyer and jurist (born 1721)
• Elizabeth Montagu, English literary critic (born 1720)
• Kazimierz Poniatowski, Polish nobleman (born 1721)
• Gabriel, African American slave and revolutionary (born 1775)
• Maciej Radziwill, Polish nobleman (born 1749)
• Baron von Riedesel, German soldier (born 1738)
• Mary Robinson, English poet (born 1756)
• Matthew Robinson, 2nd Baron Rokeby, English eccentric nobleman (born 1712)
• Charles Stewart, American revolutionary (born 1729)
• Aleksander August Zamoyski, Polish nobleman
• Théophile Corret de la Tour d'Auvergne, Grenadier officer in the French army (born 1743)

1800

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