1848

• January 24 - California gold rush: James W. Marshall finds gold at Sutter's Mill, in Coloma, near Sacramento
• January 26 - Henry David Thoreau addresses the Concord Lyceum with "The Rights and Duties of the Individual in Relation to Government" (which later came to be known as Civil Disobedience).
• February 2 - Mexican-American War: The Treaty of Guadalupe Hidalgo is signed, ending the war.
• February 2 - California Gold Rush: The first ship with Chinese emigrants seeking fortune in California's gold country arrive in San Francisco.
• February 21 - Karl Marx publishes The Communist Manifesto.
• February 24 - Abdication of Le Roi-Citoyen (citizen king) Louis Philippe, King of the French and the proclamation of the Second Republic.
• March 7 - The Great Mahele (land division) is signed in Hawaii.
• March 10 - The Treaty of Guadalupe Hidalgo is ratified by the United States Senate, ending the Mexican-American War.
• March 15 - revolution breaks out in Pest. The Habsburg rulers are compelled to meet the demands of the Reform party.
• March 20 - King Ludwig I of Bavaria abdicates
• March 29 - An upstream ice jam stops almost all water flow over Niagara Falls.
• May 19 - Mexican-American War: Treaty of Guadalupe Hidalgo - Mexico ratifies the treaty thus ending the war and ceding Texas, California and most of Arizona and New Mexico to the United States for $15 million dollars.
• May 29 - Wisconsin is admitted as the 30th U.S. state.
• July 19 - Women's rights: The two day Women's Rights Convention opens in Seneca Falls, New York and the "Bloomers" are introduced at the feminist convention.
• July 29 - Irish Potato Famine: Tipperary Revolt - In Tipperary, an unsuccessful nationalist revolt against British rule is put-down by a government police force.
• August 19 - California Gold Rush: The New York Herald breaks the news to the East Coast of the United States, that there is a gold rush in California (although the rush started in January).
• November 1 - In Boston, Massachusetts, the first medical school for women, The Boston Female Medical School (which later merged with Boston University School of Medicine), opens.
• November 3 - Greatly revised Dutch constitution proclaimed
• November 7 - U.S. presidential election, 1848: Zachary Taylor is elected president in the first US presidential election held in every state on the same day.
• December 2 - Ferdinand I, Emperor of Austria, abdicates in favor of his nephew, Franz Josef I.
• December 10 - Prince Louis-Napoleon Bonaparte elected first president of the French Second Republic.
• December 20 - President Bonaparte takes his Oath of Office in front of the French National Assembly.

• Wave of republican and democratic uprisings throughout Europe, mostly unsuccessful (see Revolution of 1848).
• Women hold Seneca Falls Convention in New York.
• Associated Press is founded.
• Boston Public Library is founded by an act of the Great and General Court of Massachusetts,
• First railway in Spain is opened, with line Barcelona to Mataró (circa 40 km).
• Illinois and Michigan Canal is completed.
• Independent Republic of Yucatan joins Mexico in exchange for Mexican help in suppressing revolt by Maya Indians.
• Serfdom is abolished in Austro-Hungarian Empire.
• John Bird Sumner becomes archbishop of Canterbury.
• British, Dutch, and German governments lay claim to New Guinea.
• Admiral Nevelskoi explores Strait of Tartary.
• Dunedin, New Zealand is founded by Scots settlers.
• University of Ottawa is founded.
• University of Mississippi is founded.
• University of Wisconsin, Madison is founded.
• Geneva College in Pennsylvania is founded.
• Holmes County, Florida is created.
• Elizabeth Gaskell publishes Mary Barton anonymously.
• Henrik Ibsen publishes first play Catilina.
• Ivar Aasen publishes Grammar of the Norwegian Dialects.
• Robert Schumann composes opera Genoveva.
• Richard Wagner begins writing libretto that will become The Ring of the Nibelung.

• Mexican-American War (1846-1848)

• 1848 in literature
  • Vanity Fair - William Makepeace Thackeray
• 1848 in science
• 1848 in music

• January 19 - John F. Stairs, businessman, statesman (+ 1904)
• February 5 - Joris-Karl Huysmans, author (+ 1907)
• February 5 - Belle Starr, outlaw (+ 1889)
• February 8 - Joel Chandler Harris, American journalist, author (+ 1908)
• February 16 - Octave Mirbeau French art critic, novelist (+ 1917)
• February 18 - Louis Comfort Tiffany, American glass artist (+ 1933)
• February 24 - Andrew Inglis Clark, Tasmanian politician (+ 1907)
• February 24 - Grant Allen, author (+ 1899)
• February 25 - Edward Harriman, railroad entrepreneur
• February 27 - Hubert Parry, English composer (+ 1918)
• March 10 - Albert Fraenkel, physician (+ 1916)
• March 19 - Wyatt Earp, policeman, gunfighter (+ 1929)
• March 31 - Viscount William Astor, British financier and statesman (+ 1919)
• May 18 - Princess Louise of the United Kingdom, fourth daughter of Queen Victoria and Prince Albert
• May 23 - Otto Lilienthal, engineer (+ 1896)
• June 7 - Paul Gauguin, French artist
• July 6 - Gabor Baross, Hungarian statesman (+ 1892).
• July 15 - Vilfredo Pareto, economist (+ 1923).
• July 22 - Winfield Scott Stratton, American miner (+ 1902)
• July 25 - George Robert Aberigh-Mackay, Anglo-Indian writer (+ 1881)
• July 25 - Arthur James Balfour, Prime Minister of the United Kingdom(+ 1930)
• November 13 - Albert I of Monaco
• November 29 - John Ambrose Fleming, English electrical engineer, inventor of Fleming valve (+ 1945)

• January 19 - Isaac D'Israeli, English author, father of Benjamin Disraeli
• February 23 - John Quincy Adams, 6th President of the United States.
• March 29 - John Jacob Astor, American businessman
• June 27 - Denis Auguste Affre, archbishop of Paris
• August 7 - Jöns Jacob Berzelius, Swedish chemist
• August 12 - George Stephenson, locomotive pioneer
• November 23 - Sir John Barrow, English statesman
• November 24 - Lord Melbourne, British Prime Minister
• December 19 - Emily Brontë, author
• Edward Baines, British newspaperman, politician
• Gaetano Donizetti, Italian opera composer