Associated Press

On July 28, 1914, a month after the assassination of Archduke Franz Ferdinand and his wife Sophie by a Serbian nationalist, the emperor of Austria-Hungary declared war on Serbia.

It was the first domino to fall in a conflict that would quickly encompass the world, drawing in countries like Germany, Russia, France, England, Canada, Japan, India and the United States and becoming known to history as World War I.

July 28, 2016, marks the 102nd anniversary of World War I. In remembrance of that anniversary and the conflict that cost more than 37 million lives, here's a photographic look at the war that would become known as The War to End All Wars.

Timeline: > July 28, 1914 - Austria-Hungary declares war on Serbia > August 1, 1914 - Germany declares war on Russia > August 3, 1914 - Germany declares war on France > August 4, 1914 - Germany declares war on Belgium > August 4, 1914 - Britain declares war on Germany > August 6, 1914 - Austria-Hungary declares war on Russia > May 7, 1915 - Germany U-boat sinks the ship Lusitania; 128 Americans die > January 19, 1917 - German telegram urges Mexico to declare war against the U.S. > April 6, 1917 - President Wilson asks Congress for a declaration of war against Germany > July 3, 1917 - First wave of the American Expeditionary Forces lands in France > November 11, 1918 - War ends as Germany and the Allies sign an Armistice > June 28, 1919 - German delegates and Allies sign the Treaty of Versailles, sowing the seeds for World War II

Read more about World War I here

Related: Soldier's story shows tragedy of World War I

Related: UK museum looks at epic, intimate sides of World War I

Related: Recently rediscovered training trenches from WWI bring the Great War to life in England

Related: For Bastille Day, France commemorates World War I >> In this 1918 file photo, American troops carrying guns with fixed bayonets climb over a sandbag revetment in France during World War One.

1914
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In this June 28, 1914 file photo, the Archduke of Austria Franz Ferdinand, center right, and his wife Sophie, center left, walk to their a car in Sarajevo. This photo was taken minutes before the assassination of the Archduke and his wife, an event which set off a chain reaction of events which would eventually lead to World War One.

1914
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In this June 28, 1914 file photo, a suspect, second right, is captured by police in Sarajevo, Yugoslavia. Princip fired the shots that assassinated Archduke Franz Ferdinand, heir to the Austrian-Hungarian throne, and his wife Sophie.

1914
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In this 1914 file photo, German army troops receive rations from a field transport while advancing toward Brussels. In mid-August 1914 the German army launched its assault on Brussels.

1914
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In this undated file photo, a British recruiting poster displays Field Marshal Herbert Kitchener in 1914. The poster reads "Your Country Needs You". Kitchener's Army was a group of all-volunteer soldiers formed in the United Kingdom.

1914
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In this August 1914 file photo, German troops stand in formation during the occupation of Brussels.

1914
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In this Aug. 8, 1914 file photo, Russian reservists walk with their belongings in St. Petersburg, Russia. Russia entered World War One with an army which was massive but badly armed.

1914
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In this Sept. 1914 file photo, the Cathedral of Reims, France smokes after bombardment during World War One. The advancing German Army heavily damaged the city.

1914
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In this 1914 file photo, small boats, pushed together, create a pontoon bridge over the Scheldt River in Antwerp, Belgium. The bridge was constructed during World War One for residents and troops to escape the German Army.

1914
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In this Oct. 14, 1914 file photo, Belgian civilians and a cavalry detail move out of the pathway of the German advance during World War One in Antwerp, Belgium.

1914
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In this 1914 file photo, German troops march through the streets of Antwerp, Belgium during World War One.

1914
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In this 1914 file photo, German soldiers gather at Christmas at an unknown location during World War One.

1914
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In this 1914 file photo, Allied troops huddle in a trench around a tiny fire near Ypres, Belgium.

1914
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In this Aug. 1914 file photo, a Belgian machine gun detachment sets up near Haelen, Belgium. The Belgians often used dogs to draw the ammunitions cart. The Battle of Haelen was also known as the Battle of the Silver Helmets.

1915
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In this May 1, 1915 file photo, the British cargo and passenger ship Lusitania as it sets out for England on its last voyage from New York City. The British ocean liner was sunk off Ireland on May 7, 1915 by a German U-Boat, killing 1,150 people, 114 of them Americans.

1915
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In this 1915 file photo, Australian troops arrive in Alexandria, Egypt, en route to the battlefield on the Gallipoli Peninsula during World War One.

1915
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In this 1915 file photo, Turkish soldiers take a rest during fighting, with their guns in their hands, in a trench in Gallipoli, Turkey.

1915
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In this 1915 file photo, a Turkish soldier takes aim at British troops, while another watches carefully, from a trench in Gallipoli, Turkey.

1915
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In this 1915 file photo, Mustafa Kemal Ataturk, military Commander of the Turkish troops in Gallipoli, Turkey, looks over the battlefield during World War One.

1915
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In this undated file photo, troops are mobilized on the bank of the Danube River across from Belgrade during World War One. Austrian forces captured the Serbian capitol on Oct. 9, 1915.

1916
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In this April 8, 1916 file photo, French soldiers move troops and cargo at Nixeville, France, during the World War One Battle of Verdun.

1916
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In this May 31, 1916 file photo, the German fleet with battle cruisers on the way in the North Sea to meet the British Grand Fleet in the Battle of Jutland during World War One.

1916
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In this May 31,1916 file photo, the British Grand Fleet under admiral John Jellicoe on their way to meet the Imperial German Navy's fleet for the Battle of Jutland in the North Sea.

1916
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In this 1916 file photo, French troops attend to the funeral of an unknown aviator at an unknown location.

1916
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In this 1916 file photo, Australian artillery soldiers operate a large caliber gun at the Somme front, in France during World War One.

1916
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In this August 1916 file photo, Gen. Sir Sam Hughes and an unidentified group look at ruins in Arras, France during World War One.

1916
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In this Sept. 24, 1916 file photo, French Captain Georges Guynemer in front of his shot-down plane in Piennes, France during World War One.

1916
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In this 1916 file photo, German troops man a machine gun post from a trench at the Vistula River in Russia during World War One.

1916
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In this 1916 file photo, German flying ace Manfred von Richthofen, also known as the "Red Baron," is shown returning from a mission at his squadron's aerodrome. Von Richthofen was shot down and killed over France in April 1918.

1916
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U.S. Lt. Dwight D. Eisenhower watches Illinois troops dig trenches during training at San Antonio, Ft. Houston, Texas, in 1916.

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A lone wounded Austrian soldier lies on the field of battle during World War One in an undated photo.

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In this undated photo, German mine-throwing troops, at an attack at the Keil and Poehl mounts, Germany.

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In this undated file photo, a Turkish cannon moves to the front lines on the Gallipoli Peninsula, Turkey, during World War One.

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In this undated file photo, a Canadian soldier helps an injured German soldier to a dressing station.

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In this undated file photo, soldiers of the French Red Cross transport a wounded soldier to a first aid station immediately after the battle of Flanders in Belgium.

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In this undated file photo, World War One wounded are being placed in ambulance during the advance on Lens, France.

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In this undated file photo, the cathedral in the town square of Ypres, Belgium, is in ruins after bombing in World War One.

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In this undated file photo, an unidentified soldier, wearing a gas mask around his neck, bangs on a frying pan as a gas warning on the field near Reims, France.

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In this undated file photo, two soldiers are passed by tanks on their way to support French troops in Juvigny, France, during World War One.

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In this undated file photo, Serbian soldiers take position on the battle line. Some of the first battles of World War One were fought between Serbia and Austria-Hungary around the Cer Mountain region.

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In this undated photo, soldiers attend a burial just in back of the battle lines in Pervyse, Belgium.

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In this undated photo, Turkish soldiers at a military review at Damascus, Syria.

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In this undated file photo World War One Belgian troops set out from Brussels in the direction of Louvain.

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In this undated file photo, one of the batteries of the famous French 75's at Douaumont, France during the World War One Battle of Verdun.

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In this undated file photo, soldiers attend the burial of fellow soldiers and two Canadian nurses, killed in German air raid, during World War One.

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In this undated file photo, British troops run under heavy fire outside Cambrai, France during World War One.

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In this undated file photo, Allied soldiers eat and drink in a shell hole in France during World War One.

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In this undated file photo, wounded World War One soldiers play a game at a London hospital.

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In this undated file photo, the U Boat 139 which sank the Lusitania in an unknown location. The British liner was sank on May 7, 1915, by a German submarine off the southern coast of Ireland. About 1,150 men, women and children, perished, 114 of which were Americans. Among those Americans who perished were Charles Frohman, Alfred G. Vanderbilt and Elbert Hubbard.

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Interior view of Fort de Vaux, one of the second fortress to fall in the Battle of Verdun, France taken during the First World War showing French soldiers resting.

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In this undated file photo, French soldiers carry the wounded during the World War One Battle of the Somme, France.

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Allied forces collect and tend to the wounded on the British front during World War I. Date and exact location are unknown.

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In this undated file photo, dancer "Mata Hari", who was born Margaretha Geertruida Zelle poses in an unknown location. Zelle was executed October 15, 1917 during World War One for spying for Germany.

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In this undated file photo, Indian troops arrive in France during World War One.

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Austrian soldier praying at the grave of a comrade during World War I in an undated photo.

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In this undated file photo, Prussian soldiers leaving Berlin for the front are given flowers by a woman during World War One.

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An incident in the British advance on Bapaume. This soldier was stitching his shirt outside a captured shelter, but was disturbed by a German shell in an undated photo.

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Austrian army with a surveying camera in an undated photo.

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In this undated photo, French troops man a lookout in France during a battle in the Argonne Forest during World War One.

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In this undated file photo, German soldiers speak with each other on the Western Front during World War One.

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In this undated file photo, German reserves being rushed to front by trucks in Germany.

1917
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In this April 2, 1917 file photo, President Woodrow Wilson delivers a speech to the joint session of Congress, in Washington, United States, during World War One.

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French airship guarding American transports in an undated photo during World War I. Location unknown.

1917
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In this 1917 photo provided by the U.S. Signal Corps, the first 5,000 American soldiers to reach England march across historic Westminster Bridge in London.

1917
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In this 1917 file photo, members of the first contingent of New Yorkers drafted into the United States Army line up in front of their barracks at Camp Upton, Yaphank, Long Island, N.Y.

1917
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In this June 13, 1917 file photo, U.S. Army General John J. Pershing, center, inspects French troops at Boulogne, France.

1917
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In this 1917 file photo, the battlefield, pockmarked with craters filled with water, after the major World War One Battle of Verdun, France.

1917
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In this 1917 file photo, German soldiers bring in Canadian wounded during the Battle of Vimy, France during World War One.

1917
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An early morning attack by British forces on the western front during the Great War, 1917.

1917
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U.S. troops of the 1st Division, the first American troops to land on French soil, parade in St. Nazaire, France, June 26, 1917 during World War I.

1917
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In this 1917 file photo, wounded Canadian and German World War One soldiers help one another through the mud during the Battle of Passchendaele in Passchendaele, Belgium.

1917
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In this 1917 file photo, World War One Canadian soldiers carry a stretcher through the mud near Boesinghe, Belgium.

1917
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In this Aug. 1917 file photo, French troops walk on regained ground near the River Meuse, near Beaumont, France during World War One.

1917
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In a shell hole during the offensive which resulted in its winning back of the Chemin des Dames in France at the end of October 1917.

1917
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Machine gunners in a shell hole during the French offensive in France, Oct. 26, 1917. Ever since April the French had been fighting to rewind the road known as the Chemin Des Dames, one of the commanding positions in the Aisne Region.

1917
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In this 1917 file photo, an unidentified World War One soldier walks along wooden planks placed over the mud of Flanders’ Fields near the Yperlee Canal near Ypres, Belgium.

1917
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In this 1917 file photo, British World War One soldiers return in formation to Ypres, Belgium.

1917
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In this Dec. 9, 1917 file photo, British General Sir Edmund Allenby enters the captured city of Jerusalem, during World War One.

1917
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In this Dec. 1917 file photo, smoke billows out of buildings in Cambrai, France, after being bombarded by German forces during the World War One Battle of Cambrai.

1917
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In this 1917 file photo, an old type tank from World War One. Tanks came into use during World War One and increased the mobility of soldiers who were mainly fighting a trench war. Their design was taken from farm vehicles.

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In this undated file photo, United States Army troops stand in the trenches in France during World War One.

1918
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In this 1918 file photo, members of the Red Cross sort the backpacks of dead and wounded soldiers in France, during World War One.

1918
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In this 1918 file photo, U.S. Marines respond to a gas attack near Verdun, France during World War One.

1918
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In this March 1918 file photo, American soldiers of Company K, 165th Infantry of the Fighting 69th, Old Rainbow Division, march to the trenches at St. Clement, France during World War One.

1918
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In this March 15, 1918 file photo, an American soldier from the First Division throws a hand grenade in battle during World War One along the Western Front in France.

1918
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A French officer advises the 117 Field Battalion Signal Corps company as they prepare to lay telephone lines in the trenches at Manonville, France, March 15, 1918, during World War I.

1918
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U.S. troops of the 168th infantry patrol near the town of Badonville, France on March 17, 1918 during World War I.

1918
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In this May 28, 1918 file photo, the 28th Infantry Regiment of the First Division, A.E.F. goes over the top of a trench during an American offensive of World War One in the Battle of Cantigny, France.

1918
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In this photo provided by the U.S. Army Signal Corps, U.S. troops aboard the S.S. Leviathan are pictured as they arrive at Brest, France, May 30, 1918, to fight in the Great War.

1918
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In this 1918 file photo, Italian army soldiers look out of their dugouts at the Battle of the Piave River, Italy during World War One. The Battle of the Piave River was fought between June 15-23, 1918.

1918
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In this 1918 file photo, Italian army soldiers look out of their dugouts at the Battle of the Piave River, Italy during World War One. The Battle of the Piave River was fought between June 15-23, 1918.

1918
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In this July 1918 file photo, American troops from the 18th Infantry, First Division, pause in a ruined French town near St. Mihiel, France during World War One.

1918
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In this Sept. 13, 1918 file photo, U.S. troops of the 107th Regiment Infantry, 27th Division, advance on a path through a barbed wire entanglement near Beauqueanes, Somme, France during World War One.

1918
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In this Sept. 26, 1918 file photo, a U.S .Army 37-mm gun crew man their position during the World War One Meuse-Argonne Allied offensive in France.

1918
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Battery "C", Sixth F.A., 1st Division which fired the first cannon shot from the U.S. on the Lorraine, France front at Beaumont during the Great War, are pictured Sept. 12, 1918.

1918
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A U.S. soldier of 5th Marine Regiment fires an anti-aircraft gun in Menaucourt, France, in 1918. Exact date is unknown.

1918
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View of 14-inch, 50 caliber U.S. Naval gun, and men ready to cover it after a day's work during the Great War in Thierville, Meuse, France, Oct. 29, 1918.

1918
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In this 1918 file photo, American troops, near St. Mihiel, France, cheer after hearing the news that the Armistice has been signed, ending World War One.

1918
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In this Nov. 11, 1918 file photo, people in the streets of Paris, France, celebrate the signing of the Armistice that ended the fighting of World War One.

1918
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In this Nov. 11, 1918 file photo, a group of people gather in front of Buckingham Palace in London, England to celebrate the signing of the Armistice that ended the fighting of World War One.

1918
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In this Nov. 1918 file photo, American soldiers from New York, who served on the frontline in Cambria, France, rig up a Liberty Bell to celebrate the signing of the Armistice to end World War One.