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World War I: Quick Facts

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News •

On this day: Armistice agreement to end World War I signed • Nov. 11, 2026, 2:13 PM ET (Jerusalem Post)
Eleven unknown Australian soldiers killed in WWI formally identified • Nov. 10, 2026, 6:30 AM ET (ABC News (Australia))
Against the odds, this teen soldier survived the horrors of WWI France and returned to Alaska • Nov. 9, 2026, 8:50 AM ET (Anchorage Daily News)
UK pays tribute to armed services members fallen in conflicts on Remembrance Sunday • Nov. 8, 2026, 10:09 AM ET (Euronews)
How a WWI hero sparked a century-old Veterans Day tradition in RI • Nov. 5, 2026, 6:01 AM ET (The Providence Journal)

Facts

Also Known As WWI • Great War • First World War
Date July 28, 1914 - November 11, 1918
Participants Bulgaria • France • Germany • Italy • Japan • Ottoman Empire • Portugal • Russia • United Kingdom • United States

Did You Know?

  • When World War 1 began in the summer of 1914, most people assumed the war would be finished by Christmas.
  • The booming of the artillery at the Western front could sometimes be heard all the way back in Britain.
  • German and British soldiers called a truce on Christmas in 1914 and played a soccer game together.

Photos and Videos

World War I
Infographic summarizing World War I with sections on the war's onset, technological firsts, and major events. Includes a timeline from 1914 to 1918, maps showing the global spread of the conflict, and pie charts displaying casualty percentages for major countries and alliances. At the bottom, two maps compare Europe's borders in 1914 and 1919. The design uses red and green tones to differentiate allies, central powers, and neutral countries.
Franz Ferdinand, archduke of Austria-Este, and his wife Sophie ride in an open carriage in Sarajevo, both dressed formally, with a man standing beside the carriage.
Maxim machine gun
Three soldiers in World War I uniforms and helmets operate a St. Etienne machine gun in a trench at the Somme.
cannon
Map illustrating the Schlieffen Plan of 1905, showing the German army's planned invasion routes at the start of World War I. Thick red arrows indicate German advances sweeping through Belgium and Luxembourg into northern France, curving toward Paris, with key cities and rivers labeled across Belgium, France, Germany, and neighboring regions.
A large group of German sailors in uniform, carrying rifles with bayonets, march in formation down a cobblestone street in Brussels, Belgium, during World War I.
Rows of British naval ships densely packed and anchored at Spithead in the English Channel, stretching to the horizon.
German World War I torpedo boats numbered 62, 64, 39, 32, and 63 are docked side by side, with uniformed sailors standing on deck and a group of officers in the foreground.
Women of World War I: Marie Curie, Mabel St. Clair Stobart, and Aileen Cole Stewart
Causes and start of World War I
See how No Man's Land between World War I trenches led to the use of chemical weapons, tanks, and warplanes
When was the motorized ambulance invented?
Learn how the Triple Entente and Triple Alliance evolved into the Allies and Central Powers in World War I
See All Videos, Images and Interactives →

Related Topics and References

Topics
Dig Deeper: More Articles That Discuss This Topic

Timeline

Historical map of the Eastern Front during World War I from 1914 to 1918, showing the farthest Russian advance in 1914, the Gallipoli campaign in 1915, the front at the time of the Russian Revolution in 1917, and the farthest Austro-German advance in 1918. The map shows Eastern Europe, including Germany, Austria-Hungary, western Russia, Romania, Bulgaria, and northern Turkey, with key cities and front lines marked.
Eastern Front
1914 - 1918
British Cavalry at the Battle of Mons
Battle of the Frontiers
August 4, 1914 - September 6, 1914
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Battle of Morhange-Sarrebourg
August 20, 1914 - August 22, 1914
Map of the Western Front during World War I from 1914 to 1918, showing northern France, Belgium, Luxembourg, and western Germany. Colored lines indicate the farthest German advance in September 1914, the front line at the beginning of 1915, German and Allied offensives, and the armistice line of 1918. Major cities such as Paris, Brussels, and Verdun, as well as key rivers and geographic features, are labeled.
Battle of Mons
August 23, 1914
Thousands of Russian prisoners of war stand in long, winding lines outdoors near buildings and trees after the Battle of Augustov in World War I.
Battle of Tannenberg
August 26, 1914 - August 30, 1914
French infantry soldiers in helmets and long coats walk through a barren, fortified trench landscape at the Marne during World War I.
First Battle of the Marne
September 6, 1914 - September 12, 1914
Ypres, Belgium
First Battle of Ypres
October 19, 1914 - November 22, 1914
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Battle of Tanga
November 2, 1914 - November 5, 1914
Falkland Islands
Battle of the Falkland Islands
December 8, 1914
Christmas Truce
Christmas Truce
December 24, 1914 - December 25, 1914
default image
battle of Gallipoli
1915
Baltic and North seas and the English Channel
Battle of Dogger Bank
January 24, 1915
Large groups of Allied soldiers gather along the shore and hillsides at Anzac Cove, Gallipoli Peninsula, with boats and piers visible in the water during the 1915 Gallipoli campaign.
Gallipoli Campaign
February 16, 1915 - January 9, 1916
The Dardanelles
naval operations in the Dardanelles Campaign
February 19, 1915 - March 18, 1915
Gas masks at the Second Battle of Ypres
Second Battle of Ypres
April 22, 1915 - May 25, 1915
French soldiers in uniform rest and eat on a grassy field behind the front lines during the Battle of Verdun in World War I, with gear and rifles stacked nearby.
Battle of Verdun
February 21, 1916 - December 18, 1916
Battle of Jutland
Battle of Jutland
May 31, 1916 - June 1, 1916
Three soldiers in World War I uniforms and helmets operate a St. Etienne machine gun in a trench at the Somme.
First Battle of the Somme
July 1, 1916 - November 13, 1916
default image
Battle of Arras
April 9, 1917 - May 17, 1917
World War I soldiers walk through muddy, debris-strewn ruins with the damaged Cloth Hall of Ypres, Belgium, standing in the background under a cloudy sky.
Battle of Passchendaele
July 31, 1917 - November 6, 1917
Cadorna, Luigi
Battle of Caporetto
October 24, 1917 - December 19, 1917
default image
Battle of Gaza
November 1917
tank in the Battle of Cambrai
Battle of Cambrai
November 20, 1917 - December 8, 1917
German Prisoners at Belleau Wood
Battle of Belleau Wood
June 1, 1918 - June 26, 1918
default image
Battle of Amiens
August 8, 1918 - August 11, 1918
John J. Pershing
Battle of Saint-Mihiel
September 12, 1918 - September 16, 1918
World War I: British army
Battle of Cambrai
September 27, 1918 - October 11, 1918
default image
Battle of Mons
November 11, 1918
Read More: World War I Timeline

Key People

default image
Sir Charles Monro
British army officer
British prime minister Winston Churchill
Winston Churchill
prime minister of United Kingdom
Kemal Atatürk
Kemal Atatürk
president of Turkey
Woodrow Wilson
Woodrow Wilson
president of United States
David Lloyd George
David Lloyd George
prime minister of United Kingdom
Portrait of Georges Clemenceau wearing a suit and a wide-brimmed hat, looking to the left with a serious expression.
Georges Clemenceau
prime minister of France
Franz Joseph
Franz Joseph
emperor of Austria-Hungary
Harry S. Truman
Harry S. Truman
president of United States
George S. Patton
George Patton
American military officer
Herbert Hoover, 1928
Herbert Hoover
president of United States
Nicholas II
Nicholas II
tsar of Russia
Kaiser Wilhelm II of Germany in military uniform, wearing a fur hat with a prominent skull emblem and various medals and decorations on his chest.
Wilhelm II
emperor of Germany
Jan Smuts.
Jan Smuts
South African statesman
Erich Ludendorff
Erich Ludendorff
German general
default image
Nikola Pašić
prime minister of Serbia
Ferdinand Foch
Ferdinand Foch
marshal of France
Asquith
H.H. Asquith, 1st earl of Oxford and Asquith
prime minister of United Kingdom
John J. Pershing
John J. Pershing
American military officer
Venizélos
Eleuthérios Venizélos
prime minister of Greece
Paul von Hindenburg
Paul von Hindenburg
president of Weimar Republic

Causes and Effects

Causes
  • A naval arms race between Great Britain and the German Empire made conflict on the high seas almost inevitable.
  • German success in the Franco-German War fostered a belief in the supremacy of Prussian militarism.
  • Germany's annexation of Alsace-Lorraine after the Franco-German War aroused a deep longing for revenge in the French people.
  • The Balkan Wars virtually eradicated the Ottoman presence in Europe, but led to violent strife among the victors.
  • The assassination of Austrian archduke Franz Ferdinand by South Slav nationalist Gavrilo Princip on June 28, 1914.
Effects
  • As many as 8.5 million soldiers and 13 million civilians died as a result of the war.
  • Failure to deliver mandated reparations leads to the armed occupation of the Ruhr River valley region by French and Belgian troops.
  • German militarists perpetuate the myth that the German Army was undefeated in battle, undermining faith in the civilian government of the Weimar Republic.
  • Imperial dynasties in Austria-Hungary, Germany, the Ottoman Empire, and Russia collapsed.
  • Mass movement of troops and refugees helped spread the Spanish flu, a devastating influenza pandemic that claimed as many as 50 million lives in 1918-19.
  • Ottoman territories in the Middle East are divvied up among the victorious Allied powers at the Conference of San Remo.
  • The League of Nations is established, but its effectiveness is hampered by the non-participation of the United States.
Read More: Causes and Effects of World War I

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