- Jan 1 Britain takes Mosquito Coast from Nicaragua
- Jan 3 Joseph Jenkins Roberts is sworn in as the first President of the independent African Republic of Liberia
- Jan 8 Austrian soldiers kill 10 students, Pavia
California Gold Rush
Jan 24 James Marshall finds gold in Sutter's Mill in Coloma, California[1]
- Jan 28 King of Naples grants his subjects a constitution
- Jan 29 Sicily accepts new Constitution (choose parliament/freedom of press)
- Feb 2 1st Chinese immigrants arrive by boat in San Francisco, California
- Feb 2 Treaty of Guadalupe Hidalgo ends the Mexican–American War. Mexico loses 55 percent of its territory to the US, including California, Nevada and Utah in exchange for $15 million.
- Feb 12 Choreographer Jules Perrot's ballet "Faust" to music by Giacomo Panizza and Michael Andrew Costa, premieres at La Scala Teatro in Milan, Kingdom of Lombardy
- Feb 15 Sarah Roberts barred from white school in Boston
- Feb 17 Tuscany gets liberal Constitution
The Communist Manifesto
Feb 21Karl Marx andFriedrich Engels publish "The Communist Manifesto" in London
- Feb 24 King Louis-Philippe abdicates, 2nd French republic declared
- Feb 26 2nd French Republic proclaimed
- Feb 29 The Principality of Neuchâtel declares itself independent of Prussia
- Mar 1 10th Grand National: Capt. Josey Little aboard 12/1 Chandler wins; race marred by fatal falls of 3 competitors
- Mar 4 Carlo Alberto di Savoia signs the Statuto Albertino that will later represent the first constitution of the Regno d'Italia
- Mar 4 Sardinia-Piemonte gets new Constitution
- Mar 5 Louis Antoine Garnier-Pages is named French minister of Finance
- Mar 7 In Hawaii, Great Mahele (division of lands) signed
- Mar 11 Louis-Hippolyte Lafontaine and Robert Baldwin become the first Prime Ministers of the Province of Canada to be democratically elected under a system of responsible government
- Mar 12 2nd Republic established in France
- Mar 15 A revolution breaks out in Hungary. The Habsburg rulers are compelled to meet the demands of the Reform party.
- Mar 23 The ship John Wickliffe arrives at Port Chalmers carrying the first Scottish settlers for Dunedin, New Zealand. Otago province is founded.
- Mar 24 State of siege proclaimed in Amsterdam
- Mar 27 John Parker Paynard originates medicated adhesive plaster
Niagara Falls Stops Flowing
Mar 29 Niagara Falls stops flowing for 30 hours due to an ice jam in the river upstream
Senator Horace Mann
Apr 3 American education reformerHorace Mann joins the US Senate, representing Massachusetts
Leichhardt Disappears
Apr 3 German explorerLudwig Leichhardt is seen for the last time at McPherson's Station, Coogoon, before he disappears on the same expedition to reach the Swan River in Australia[1]
- Apr 3 Thomas Douglas becomes 1st public teacher in San Francisco
- Apr 6 Jews of Prussia granted equality
- Apr 8 1st battle at Gioto: Sardinia-Piemonte beats Austrians
- Apr 8 Battle at Xaquixaguana, Peru: Pedro de la Gasca beats Gonzalo Pizarro
- Apr 11 Hungary becomes constitutional monarchy under King Ferdinand of Austria
- Apr 18 American victory at the battle of Cerro Gordo opens the way for invasion of Mexico
- Apr 22 Captain James Fitzjames and 105 surviving crew depart their ice-trapped ships for safety in arctic Canada - all later perish. Part of John Franklin's doomed Northwest Passage expedition.[1]
Alfred Wallace for South America
Apr 26Alfred Russel Wallace departs the U.K. for South America, beginning four years of travel, collecting, and research in the region
- Apr 28 Slavery abolished in French colonies
- May 1 The Fraternity of Phi Gamma Delta is founded at Jefferson College in Canonsburg, Pennsylvania
- May 6 Otto Tank ends slavery in Suriname colony
- May 7 Prussians stop insurrection in Varsovia
- May 13 First performance of Finland's national anthem "Maamme", composed by Fredrik Pacius, Swedish words by Johan Ludvig Runeberg
- May 17 Gerrit, Count Schimmelpenninck resigns as Chairman of the Council of Ministers of Netherlands
- May 18 Opening of the first German National Assembly (Nationalversammlung) in Frankfurt, Germany
- May 29 Battle at Curtazone: Austrians beat Sardinia-Piemonte
- May 29 Wisconsin becomes 30th US state
- May 30 Second Battle at Gioto: Sardinia-Piemonte beats Austrians
- May 30 Treaty of Guadalupe Hidalgo between the United States and Mexico comes into force, giving California Nevada, Utah and most of Colorado, New Mexico and Arizona to the US in return for $15 million
- May 30 William G Young patents ice cream freezer
- Jun 1 Revolutionary newspaper "Neue Rheinische Zeitung" founded byKarl Marx, Friedrich Engels and the Communist League in Cologne
- Jun 2 The Slavic congress in Prague begins.
Statue of William the Silent
Jun 5 Statue of princeWilliam the Silent, Prince of Orange by Lodewyk Royer unveiled in The Hague's Het Plein
Martin Van Buren Nominated
Jun 22 Barnburners (anti-slavery) party nominatesMartin Van Buren for President
- Jun 22 Beginning of the June Days uprising in Paris by French workers
- Jun 23 Bloody insurrection of workers in Paris
- Jun 26 1st pure food law enacted in US
- Jun 26 End of the June Days uprising in Paris by French workers
- Jul 3 Slaves freed in Danish West Indies (now US Virgin Islands)
- Jul 11 Edmund Hickly gets 1st known 10 wicket innings (Kent v England)
- Jul 11 London's Waterloo Station opens
1st US Women's Rights Convention
Jul 19 First US women's rights convention held in Seneca Falls, NY, organized byElizabeth Cady Stanton and Lucretia Mott
- Jul 19 German Parliament demands Dutch province of Limburg
- Jul 23 Battle of Custoza-Italian War of Independence, starts
- Jul 25 1st battle at Custozza: Austrians under Radetzky beat Italian
- Jul 29 Irish Potato Famine: Tipperary Revolt - an unsuccessful nationalist revolt against British rule put down by police
- Aug 9 Austria and Sardinia sign a ceasefire
- Aug 9 US Barnburners (anti-slavery) party merges with Free Soil Party nominatingMartin Van Buren for president
- Aug 14 Oregon Territory created
- Aug 15 M. Waldo Hanchett patents dental chair
- Aug 18 Camila O'Gorman and Ladislao Gutierrez are executed on the orders of Argentine dictator Juan Manuel de Rosas
Gold Discovered in California
Aug 19New York Herald is the first major eastern newspaper to report the discovery of gold in California
- Aug 22 The United States annexes New Mexico
- Sep 6 National Black Convention meets in Cleveland
- Sep 12 Switzerland becomes a Federal state
- Sep 14 Alexander Stewart opens the 1st US department store, “The Marble Palace” in downtown New York City
- Sep 16 Slavery is abolished in all French territories
- Sep 18 Baseball rules 1st baseman can tag base for out instead of runner
- Sep 19 Hyperion, moon of Saturn - the first non-round moon - discovered by William Cranch Bond, his son George Phillips Bond and William Lassell
- Sep 20 American Association for the Advancement of Science is founded
- Sep 29 Battle of Pákozd: Hungarian forces defeat Croats at Pákozd; the first battle of the War of Independence
- Oct 16 1st US homeopathic medical college opens in Pennsylvania
- Oct 28 The first railroad in Spain opens, between Barcelona and Mataró
- Nov 1 Classes begin at Boston Female Medical College, 1st US female medical college
WHSmith: a Retail Giant Born From a Widow's Might
Nov 1 WHSmith opens its 1st railway bookstall, at Euston Station in London, England
- Nov 3 Johan Thorbeckes revises the Constitution of the Netherlands
Zachery Taylor
Nov 7 GeneralZachary Taylor elected as 12th President of US
Franz Joseph I
Dec 2Franz Joseph I proclaimed Emperor of Austria and King of Hungary, Croatia and Bohemia at Olmütz after the abdication of his uncle Ferdinand I
California Gold Rush
Dec 5 US PresidentJames K. Polk triggers the Gold Rush of 1849 by confirming a gold discovery in California
- Dec 25 New Haven Railroad opens
- Dec 25 William & Ellen Craft escape from slavery in Georgia, arriving in Philadelphia, Pennsylvania; later move to Boston where they become abolitionists[1]
- Dec 26 1st gold seekers arrive in Panama en route to San Francisco
- Dec 26 The Phi Delta Theta fraternity is founded at Miami University, Oxford, Ohio.
- Dec 29 Gas lights 1st installed at White House (Polk's administration)