World War IFacts, information and articles about World War I, aka The Great War

The war fought between July 28, 1914, and November 11, 1918, was known at the time as the Great War, the War to End War, and (in the United States) the European War. Only when the world went to war again in the 1930s and ’40s did the earlier conflict become known as the First World War. Its casualty totals were unprecedented, soaring into the millions. World War I is known for the extensive system of trenches from which men of both sides fought. Lethal new technologies were unleashed, and for the first time a major war was fought not only on land and on sea but below the sea and in the skies as well. The two sides were known as the Allies or Entente—consisting primarily of France, Great Britain, Italy, Russia, and later the United States—and the Central Powers, primarily comprised of Austria-Hungary (the Habsburg Empire), Germany, and the Ottoman Empire (Turkey). A number of smaller nations aligned themselves with one side or the other. In the Pacific Japan, seeing a chance to seize German colonies, threw in with the Allies. The Allies were the victors, as the entry of the United States into the war in 1917 added an additional weight of men and materiel the Central Powers could not hope to match.

The war resulted in a dramatically changed geo-political landscape, including the destruction of three empires: Austro-Hungarian, Ottoman and Russian. New borders were drawn at its conclusion and resentments, especially on the part of Germany, left festering in Europe. Ironically, decisions made after the fighting ceased led the War to End War to be a significant cause of the Second World War.

As John Keegan wrote in The First World War (Alfred A. Knopf, 1999), “The First World War was a tragic and unnecessary conflict … the train of events that led to its outbreak might have been broken at any point during the five weeks of crisis that preceded the first clash of arms, had prudence or common goodwill found a voice.”

Casualties in World War I

In terms of sheer numbers of lives lost or disrupted, the Great War was the most destructive war in history until it was overshadowed by its offspring, the Second World War: an estimated 10 million military deaths from all causes, plus 20 million more crippled or severely wounded. Estimates of civilian casualties are harder to make; they died from shells, bombs, disease, hunger, and accidents such as explosions in munitions factories; in some cases, they were executed as spies or as “object lessons.” Additionally, as Neil M. Heyman in World War I (Greenwood Press, 1997) wrote, “Not physically hurt but scarred nonetheless were 5 million widowed women, 9 million orphaned children, and 10 million individuals torn from their homes to become refugees.” None of this takes into account the deaths in the Russian Civil War or the Third Balkan War, both of which directly resulted from World War I, nor the Spanish influenza pandemic of 1918 that killed 50 million people worldwide, which was spread in part by conditions at the front and by soldiers returning home.

The highest national military casualty totals—killed, wounded, and missing/taken prisoner—in round numbers (sources disagree on casualty totals), were:

• Russia: 9,150,000

• Germany: 7,143,000

• Austria-Hungary: 7,000,000

• France, 6,161,000

• Britain & Commonwealth: 3,190,000

• Italy: 2,197,000

• Turkey (Ottoman Empire): 975,000

• Romania: 536,000

• Serbia: 331,000

• USA: 323,000

• Bulgaria: 267,000

For more information, click to see the Casualties of World War I.

Causes of World War I

Prime Minister of Germany Otto von Bismarck had prophesied that when war again came to Europe it would be over “some damn foolish thing in the Balkans.” Indeed, the assassination of Archduke Franz Ferdinand, heir apparent to the Habsburg throne of Austria-Hungary, and his wife, Sophie, by a Serbian nationalist on June 28, 1914, was the match that lit the fuse—but it didn’t create the powder keg. The outbreak of war between European nations was the result of several factors:

• Concern over other countries’ military expansion, leading to an arms race and entangling alliances

• Fear of losing economic and/or diplomatic status

• Long-standing ethnic differences and rising nationalism in the Balkans

• French resentment of territorial losses in the 1871 Franco-Prussian War

• The influence exerted by military leaders

Following their 1871 victory in the Franco-Prussian War, the German states unified into a single nation. Its leader, Kaiser Wilhelm II, eldest grandson of Britain’s Queen Victoria, envisioned an Imperial Navy that could rival Great Britain’s large and renowned fleet. This would increase German influence in the world and likely allow the country to expand its colonial holdings. Britain, fearful of losing its dominance of the seas, accelerated its naval design and construction to stay ahead of the Kaiser’s ship-building program.

Russia was rebuilding and modernizing its large army and had begun a program of industrialization. Germany and Austria-Hungary saw the threat posed by Russia’s large population and, hence, its ability to raise a massive army. They formed an alliance for self-protection against the Russian bear.

France, still stinging over the loss of Alsace and part of Lorraine in the Franco-Prussian war, made an agreement allying itself with Russia in any war with Germany or Austria-Hungary. Britain, after finding itself friendless during the Second Boer War in South Africa (1899–1902) allied itself with France and worked to improve relations with the United States of America. Russia, with many ethnic groups inside its vast expanse, made an alliance with Serbia in the Balkans.

The old Ottoman Empire was crumbling; “The Sick Man of Europe” was the phrase used to describe the once-powerful state. As its ability to exert control over its holdings in the Balkans weakened, ethnic and regional groups broke away and formed new states. Rising nationalism led to the First and Second Balkan Wars, 1912 and 1913. As a result of those wars, Serbia increased its size and began pushing for a union of all South Slavic peoples. Serbian nationalism led 19-year-old Gavrilo Princip to assassinate Archduke Franz Ferdinand, heir apparent to the Habsburg throne of Austria-Hungary, and his wife, Sophie. Austria-Hungary, urged on by Germany, sent a list of demands to Serbia in response; the demands were such that Serbia was certain to reject them. When it did, the Habsburg Empire declared war on Serbia on July 28, exactly one month after the archduke’s assassination. Russia came in on the side of the Serbs, Germany on the side of the Habsburgs, and the entangling alliances between the nations of Europe pulled one after another into the war. Although diplomats throughout Europe strove to settle matters without warfare right up to the time the shooting started, the influence military leaders enjoyed in many nations won out—along with desires to capture new lands or reclaim old ones.

Combat in the First World War

German military planners were ready when the declarations of war began flying across Europe. They intended to hold off the Russians in the east, swiftly knock France out of the war through a maneuver known as the Schliefffen Plan, then throw their full force, along with Austria-Hungary, against the Russians. The Schliefffen Plan, named for General Count Alfred von Schlieffen who created it in 1905, called for invading the Low Countries (Luxembourg and Belgium) in order to bypass to the north the strong fortifications along the French border. After a rapid conquest of the Low Countries, the German advance would continue into northern France, swing around Paris to the west and capture the French capital. It almost worked, but German commander in chief General Helmuth von Moltke decided to send his forces east of Paris to engage and defeat the weakened French army head-on. In doing so he exposed his right flank to counterattack by the French and a British Expeditionary Force, resulting in the First Battle of the Marne, September 6–10, 1914. Despite casualties in the hundreds of thousands, the battle was a stalemate, but it stopped the German drive on Paris. Both sides began digging a network of trenches. The First Battle of the Marne was a window onto how the rest of the war would be fought: extensive trenchworks against which large numbers of men would be hurled, suffering extremely high casualties for little if any territorial gains. The centuries-old method of massed charges to break through enemy positions did not work when the men faced machine guns, barbed wire, and drastically more effective artillery than in the past.

The next four years would see battles in which millions of artillery shells were fired and millions of men were killed or mutilated. Click here to read about some of the costliest battles of the First World War. Deadly new weapons were responsible for the unprecedented carnage.