1858 1859 1860 - 1861 - 1862 1863 1864
| Decades: |
1830s 1840s 1850s - 1860s - 1870s 1880s 1890s
| Centuries: |
18th century - 19th century - 20th century
- January 1 - [[Benito Ju�rez]] captures Mexico City
- January 2 - Friedrich Wilhelm IV of Prussia dies and is succeeded by Wilhelm I
- January 3 - American Civil War: Delaware votes not to secede from the United States
- January 9 - Mississippi becomes the second state to secede from the Union, preceding the American Civil War.
- January 10 - American Civil War: Florida secedes from the United States
- January 11 - American Civil War: Alabama secedes from the United States
- January 18 - American Civil War: Georgia joins the Confederacy
- January 21 - American Civil War: Jefferson Davis resigns from the United States Senate
- January 26 - American Civil War: Louisiana secedes from the Union.
- January 29 - Kansas is admitted as the 34th U.S. state.
- February 1 - American Civil War: Texas secedes from the United States.
- February 4 - American Civil War: In Montgomery, Alabama the Confederate States of America is formed by delegates from six break-away United States.
- February 8 - American Civil War: The Confederate States of America are formed.
- February 9 - American Civil War: Jefferson Davis is elected the Provisional President of the Confederate States of America by the Confederate convention at Montgomery, Alabama.
- February 11 - American Civil War: US House unanimously passes resolution guaranteeing non-interference with slavery in any state.
- February 18 - American Civil War: In Montgomery, Alabama Jefferson Davis is inaugurated as the provisional president of the Confederate States of America.
- February 18 - Victor Emmanuel of Savoy becomes King of Italy
- February 19 - Serfdom is abolished in Russia.
- February 23 - President-elect Abraham Lincoln arrives secretly in Washington, DC after an assassination attempt in Baltimore, Maryland.
- February 27 - A crowd in Warsaw protesting Russian rule over Poland is fired upon by Russian troops killing five protesters.
- February 28 - Colorado is organized as a United States territory.
- March 2 - Nevada is organized as a United States territory.
- March 3 - Formal emancipation of the serfs in Imperial Russia
- March 4 - End of term for President of the United States James Buchanan. He is succeeded by Abraham Lincoln.
- March 4 - American Civil War: The "Stars and Bars" is adopted as the flag of the Confederate States of America.
- March 11 - American Civil War: The Constitution of the Confederate States of America is adopted.
- March 17 - Proclamation of the kingdom of Italy with Victor Emanuel II as its king
- March 19 - First Taranaki War ends in New Zealand
- March 30 - Sir William Crookes announces his discovery of Thallium (see Discovery of the chemical elements)
- April 12 - American Civil War begins at Fort Sumter, South Carolina
- April 27 - American Civil War: President Abraham Lincoln suspends the writ of habeas corpus in the United States.
- April 27 - American Civil War: West Virginia secedes from Virginia.
- May 6 - American Civil War: Arkansas secedes from the Union.
- May 7 - American Civil War: Tennessee secedes from the Union.
- May 8 - American Civil War: Richmond, Virginia is named the capital of the Confederate States of America.
- May 13 - American Civil War: Victoria of the United Kingdom issues a "proclamation of neutrality" which recognizes the breakaway states as having belligerent rights.
- May 20 - American Civil War: Kentucky proclaims its neutrality which will last until September 3 when Confederate forces enter the state. North Carolina secedes from the United States
- June 8 - American Civil War: Tennessee secedes from the Union.
- June 9 - Lebanon separated from Syrian administration and reunited under Ottoman governor with the approval of European powers
- June 15 - [[Benito Ju�rez]] formally elected president of Mexico; he temporarily stops the payments of foreign debt
- June 25 - Abd-ul-Mejid, Sultan of the Ottoman Empire (1839-1861) dies and is succeeded by Abd-ul-Aziz (1861-1876).
- July 2 - Ioan Kasatkin lands on Hakodate and introduces the Eastern Orthodox church into Japan.
- July 21 - American Civil War: First Battle of Bull Run - At Manassas Junction, Virginia, the first major battle of the war begins (Confederate victory).
- July 25 - American Civil War: The Crittenden-Johnson Resolution is passed by the United States Congress stating that the war is being fought to preserve the Union and not to end slavery.
- July 26 - American Civil War: George McClellan assumes command of the Army of the Potomac following a disastrous Union defeat at the First Battle of Bull Run.
- August 5 - American Civil War: In order to help pay for the war effort, the United States government issues the first income tax as part of the Revenue Act of 1861 (3% of all incomes over US $800; rescinded in 1872).
- August 27 - Last execution in Britain for attempted murder - Martin Doyle in Chester
- September 3 - American Civil War: Confederate General Leonidas Polk invades neutral Kentucky, prompting the state legislature to ask for Union assistance.
- September 6 - American Civil War: Forces under Union General Ulysses S. Grant bloodlessly capture Paducah, Kentucky, which gives the Union control the mouth of the Tennessee River.
- October 21 - American Civil War: Battle of Ball's Bluff - Union forces under Colonel Edward Baker are defeated by Confederate troops in the second major battle of the war. Baker, a close friend of Abraham Lincoln, is killed in the fighting.
- October 31 - American Civil War: Citing failing health, Union General Winfield Scott resigns as Commander of the United States Army.
- November 1 - American Civil War: US President Abraham Lincoln appoints George McClellan as commander of the Union Army, replacing the aged General Winfield Scott.
- November 2 - American Civil War: Western Department Union General John C. Fremont is relieved of command and replaced by David Hunter.
- November 6 - American Civil War: Jefferson Davis is elected president of the Confederate States of America.
- November 7 - American Civil War: Battle of Belmont - In Belmont, Missouri, Union forces led by General Ulysses S. Grant overrun a Confederate camp but are forced to retreat when Confederate reinforcements arrive.
- November 8 - American Civil War: The "Trent Affair" - The USS San Jacinto stops the United Kingdom mail ship Trent and arrests two Confederate envoys, James Mason and John Slidell, sparking a diplomatic crisis between the UK and US.
- November 21 - American Civil War: Confederate President Jefferson Davis appoints Judah Benjamin secretary of war.
- News of Henri Mouhot's discovery of Angkor Wat published
- In Britain, the death penalty is limited to murder, embezzlement, piracy and arson in a docks or in an ammunition depot
- British Empire establishes bases in Lagos to stop the slave trade
- January 14 - Sultan Mehmed VI of the Ottoman Empire (+ 1926)
- February 12 - Lou Andreas-Salome, author (+ 1937)
- February 26 - King Ferdinand of Bulgaria (+ 1948)
- February 27 - Rudolf Steiner, anthroposoph (+ 1925)
- April 8 - Son, Byong-Hi, one of the leaders of the Samil, or March 1st Movement in Korea
- April 15 - Bliss Carman, poet
- May 6 - Rabindranath Tagore
- October 16 - J. B. Bury
- October 30 - Antoine Bourdelle, sculptor
- December 4 - Lillian Russell, singer, vaudeville star (d. 1922)
- November 6 - James Naismith, inventor of basketball
- December 8 - [[Georges M�li�s ]], French film director, allegedly the first.
- December 16 - Antonio de La Gandara, painter
- December 20 - Ivana Kobilca, Slovene painter (+ 1926)
- January 2 - Friedrich Wilhelm IV, king of Prussia
- January 17 - Lola Montez (adventurer)
- May 29 - Joachim Lelewel , Polish nationalist historian.
- June 25 - Abd-ul-Mejid, Ottoman sultan
- July 25 - Jonas Furrer, Swiss Federal Councilor
- December 14 - Prince Albert of Saxe-Coburg-Gotha, Prince Consort, husband of Queen Victoriaaf:1861