1861 1862 1863 - 1864 - 1865 1866 1867
1830s 1840s 1850s - 1860s - 1870s 1880s 1890s
Events of 1864
- January 16 – Denmark rejects a Prussian-Austrian ultimatum to repeal the Danish Constitution.
- January 21 – Māori Wars: The Tauranga Campaign starts.
- February 1 – Danish-Prussian War (Second war of Schleswig): 57,000 Austrian and Prussian troops cross the Eider River into Denmark.
- February 17 – American Civil War: The tiny Confederate submarine H.L. Hunley attacks the USS Housatonic with a spar torpedo, becoming the first submarine to sink an enemy ship (the sub and her crew of 8 are also lost).
- February 25 – American Civil War: The first Northern prisoners arrive at the Confederate prison at Andersonville, Georgia (the 500 prisoners had left Richmond, Virginia 7 days before).
- March 1- Alejandro Mon Menéndez takes office as Prime Minister of Spain.
- March 9- American Civil War: Abraham Lincoln appoints Ulysses S. Grant commander in chief of all Union armies.
- March 10 – American Civil War: The Red River Campaign begins as Union troops reach Alexandria, Louisiana.
- March 11 – A reservoir near Sheffield, England bursts; 250 die.
- April 18 – Danish-Prussian War (Second War of Schleswig) – Battle of Dybbøl: The Prussian army fielding 10,000 men defeats the Danish defending army of 9,200 at Dybbøl Mill, after an artillery bombardment from April 7 to April 18.
- April 22 – The U.S. Congress passes the Coinage Act of 1864 which mandates that the inscription "In God We Trust" be placed on all coins minted as United States currency.
- May 5 – American Civil War: The Battle of the Wilderness begins in Spotsylvania County, Virginia.
- May 7 – American Civil War: The Army of the Potomac, under General Ulysses S. Grant, breaks off from the Battle of the Wilderness and moves southwards.
- May 11 – American Civil War – Battle of Yellow Tavern: Confederate General JEB Stuart is mortally wounded at Yellow Tavern, Virginia.
- May 12 – American Civil War – Battle of Spotsylvania Court House: The "Bloody Angle" – thousands of Union and Confederate soldiers die.
- May 13 – American Civil War – Battle of Resaca: The battle begins with Union General Sherman fighting toward Atlanta.
- May 18 – Civil War gold hoax: The New York World and the New York Journal of Commerce publish a fake proclamation that President Abraham Lincoln has issued a draft of 400,000 more soldiers.
- May 20 – American Civil War – Battle of Ware Bottom Church: In the Virginia Bermuda Hundred Campaign, 10,000 troops fight in this Confederate victory.
- May 21 – Circassian leaders sign Russian loyalty oaths, ending the Russian-Circassian War.
- May 28 – Montana is organized as a United States territory out of parts of Washington Territory and Dakota Territory, and is signed into law by President Abraham Lincoln.
- June 5 – American Civil War – Battle of Piedmont: Union forces under General David Hunter defeat a Confederate army at Piedmont, West Virginia, taking nearly 1,000 prisoners.
- June 10 – American Civil War: Battle of Noonday Creek near Kennesaw, Georgia.
- June 10 – American Civil War – Battle of Brice's Crossroads: Confederate troops under Nathan Bedford Forrest defeat a much larger Union force led by General Samuel D. Sturgis in Mississippi.
- June 12 – American Civil War – Battle of Cold Harbor: General Ulysses S. Grant pulls his troops from their positions at Cold Harbor, Virginia and moves south.
- June 15 – Arlington National Cemetery is established when 200 acres (0.8 km²) of the grounds of Robert E. Lee's home Arlington House are officially set-aside as a military cemetery by U.S. Secretary of War Edwin M. Stanton.
- American Civil War – Battle of Petersburg: Union forces under General Grant and troops led by Confederate General Robert E. Lee battle for the last time.
- June 21 – Māori Wars: The Tauranga Campaign ends.
- June 27 – American Civil War: Battle of Kennesaw Mountain near Kennesaw, Georgia.
- July 18 – President Lincoln issues a true proclamation of conscription of 500,000 men for the U.S. Civil War.
- July 20 – American Civil War – Battle of Peachtree Creek: Near Atlanta, Georgia, Confederate forces led by General John Bell Hood unsuccessfully attack Union troops under General William T. Sherman.
- July 22 – American Civil War – Battle of Atlanta: Outside of Atlanta, Georgia, Confederate General Hood leads an unsuccessful attack on Union troops under General Sherman on Bald Hill.
- July 24 – American Civil War – Battle of Kernstown: Confederate General Jubal Early defeats Union troops led by General George Crook in an effort to keep the Yankees out of the Shenandoah Valley.
- July 28 – American Civil War – Battle of Ezra Church: Confederate troops led by General Hood make a third unsuccessful attempt to drive Union forces under General Sherman from Atlanta, Georgia.
- July 29 – American Civil War: Confederate spy Belle Boyd is arrested by Union troops and detained at the Old Capitol Prison in Washington, DC.
- July 30 – American Civil War – Battle of the Crater: Union forces attempt to break Confederate lines by exploding a large bomb under their trenches.
- August 1 – The Elgin Watch Company is founded in Elgin, Illinois.
- August 5 – American Civil War – Battle of Mobile Bay: At Mobile Bay near Mobile, Alabama, Admiral David Farragut leads a Union flotilla through Confederate defenses and seals one of the last major Southern ports.
- August 13 – The first fish and chips shop opens in London.
- August 18 – American Civil War – Battle of Globe Tavern: Forces under Union General Ulysses S. Grant try to cut a vital Confederate supply-line into Petersburg, Virginia, by attacking the Weldon Railroad, forcing the Confederates to use wagons.
- August 22 – First Geneva Convention: The International Red Cross is founded.
- August 31 – American Civil War: Union forces led by General William T. Sherman launch an assault on Atlanta, Georgia.
- September 1 -American Civil War: Confederate General Hood evacuates Atlanta after a 4-month siege mounted by Union General Sherman.
- September 2 – American Civil War: Union forces under General Sherman enter Atlanta a day after the Confederate defenders fled the city.
- September 7 – American Civil War: Atlanta, Georgia is evacuated on orders of Union General William Tecumseh Sherman.
- September 8 – Delegates from the Canadian colonies meet at the Charlottetown Conference to discuss the Canadian Confederation.
- September 28 – The International Workingmen's Association was founded in London.
- October 2 – American Civil War – Battle of Saltville: Union forces attack Saltville, Virginia but are defeated by Confederate troops.
- October 5 – A cyclone kills 70,000 in Calcutta, India.
- October 9 – American Civil War – Battle of Tom's Brook: Union cavalrymen in the Shenandoah Valley defeat Confederate forces at Tom's Brook, Virginia.
- October 28 – American Civil War – Second Battle of Fair Oaks: Union forces under General Ulysses S. Grant withdraw from Fair Oaks, Virginia, after failing to breach the Confederate defenses around Richmond, Virginia.
- October 30
- The Second war of Schleswig is concluded. Denmark renounces all claim to Schleswig, Holstein and Lauenburg, which come under Prussian and Austrian administration.
- Helena, Montana is founded after four prospectors (the so-called Four Georgians) discover gold at Last Chance Gulch; it is their last and agreed final attempt at weeks of trying to find gold in the northern Rockies.
- October 31 – Nevada is admitted as the 36th U.S. state.
- November 4 – American Civil War – Battle of Johnsonville: At Johnsonville, Tennessee, troops under the command of Confederate General Nathan Bedford Forrest bombard a Union supply base with artillery and destroy millions of dollars in material.
- November 7 – The capital of Idaho Territory is moved from Lewiston to Boise; North Idaho declares the move illegal and proposes secession.
- November 8 – U.S. presidential election, 1864: Abraham Lincoln is reelected in an overwhelming victory over George B. McClellan.
- November 15 – American Civil War – Sherman's March to the Sea begins: Union General Sherman burns Atlanta and starts to move south, causing extensive devastation to crops and mills and living off the land.
- November 20 – The Judicial reform of Alexander II is launched in Imperial Russia.
- November 22 – American Civil War – Sherman's March to the Sea: Confederate General John Bell Hood invades Tennessee in an unsuccessful attempt to draw Union General Sherman from Georgia.
- November 25 – American Civil War: A group of Confederate operatives calling themselves the Confederate Army of Manhattan starts fires in more than 20 locations in an unsuccessful attempt to burn down New York City.
- November 29 – Indian Wars – Sand Creek Massacre: Colorado volunteers led by Colonel John Chivington massacre at least 400 Cheyenne and Arapahoe noncombatants at Sand Creek, Colorado (where they had been given permission to camp).
- November 30 – American Civil War – Second Battle of Franklin: The Army of Tennessee led by General Hood mounts a dramatically unsuccessful frontal assault on Union positions around Franklin, Tennessee (Hood loses 6 generals and almost a third of his troops).
- December 4 – American Civil War – Sherman's March to the Sea: At Waynesboro, Georgia, forces under Union General Judson Kilpatrick prevent troops led by Confederate General Joseph Wheeler from interfering with Union General Sherman's campaign of destroying a wide swath of the South on his march to Savannah, GA (Union forces suffer more than 3 times the casualties as the Confederates, however).
- December 8 – Syllabus errorum: Pope Pius IX condemns theological liberalism as an error and claims for the supremacy of Roman Catholic Church authority over the civil society. He also condemns rationalism and socialism.
- December 15–16 – American Civil War – Battle of Nashville: Union forces decisively defeat the Confederate Army of Tennessee.