Outbreak of World War I Summary

  • Last updated on November 10, 2022

The outbreak of World War I began a conflict that contributed to the collapse of the Russian, German, and Austrian empires, weakened Great Britain and France and their colonial empires, catapulted the United States to a dominant position in world affairs, and set the stage for an even more devastating world war.

Summary of Event

The assassination Assassinations;Francis Ferdinand of Archduke Francis Ferdinand, heir to the Austro-Hungarian throne, on June 28, 1914, set in motion a chain of events that resulted in a world war that profoundly affected the course of history. Virtually since that time, historians have attempted to explain how such a relatively minor event as the assassination could have had such devastating consequences. The war not only ravaged the economies of the major European states but also caused or made possible the triumph of communism in Russia, the rise of Nazism in Germany, and the international anarchy that led to World War II. Not least, World War I resulted in the deaths of between ten million and twenty million people. World War I (1914-1918)[World War 01];outbreak [kw]Outbreak of World War I (June 28-Aug. 4, 1914) [kw]World War I, Outbreak of (June 28-Aug. 4, 1914) [kw]War I, Outbreak of World (June 28-Aug. 4, 1914) World War I (1914-1918)[World War 01];outbreak [g]Austria;June 28-Aug. 4, 1914: Outbreak of World War I[03540] [g]England;June 28-Aug. 4, 1914: Outbreak of World War I[03540] [g]Europe;June 28-Aug. 4, 1914: Outbreak of World War I[03540] [g]France;June 28-Aug. 4, 1914: Outbreak of World War I[03540] [g]Germany;June 28-Aug. 4, 1914: Outbreak of World War I[03540] [g]Hungary;June 28-Aug. 4, 1914: Outbreak of World War I[03540] [g]Russia;June 28-Aug. 4, 1914: Outbreak of World War I[03540] [g]United States;June 28-Aug. 4, 1914: Outbreak of World War I[03540] [c]Diplomacy and international relations;June 28-Aug. 4, 1914: Outbreak of World War I[03540] [c]Government and politics;June 28-Aug. 4, 1914: Outbreak of World War I[03540] [c]Wars, uprisings, and civil unrest;June 28-Aug. 4, 1914: Outbreak of World War I[03540] [c]World War I;June 28-Aug. 4, 1914: Outbreak of World War I[03540] Francis Ferdinand Berchtold, Leopold von Bethmann Hollweg, Theobald von Grey, Sir Edward Sazonov, Sergey Dmitriyevich William II Nicholas II [p]Nicholas II[Nicholas 02];World War I[World War 01] Izvolsky, Aleksandr Petrovich

After the assassination of Francis Ferdinand, the chief of staff of the Austro-Hungarian army recommended that his emperor, Franz Joseph, mobilize his army on the border between Austria-Hungary and Serbia. The chief of staff argued along with civilian members of Franz Joseph’s government that members of the Serbian government and armed forces had helped plan and carry out the assassination. He noted that individuals within the Serbian government, desirous of incorporating into their own territory the part of the Austrian Empire that contained a large Serbian population, had good reason to wish the Austrian heir dead.

Austrian foreign minister Leopold von Berchtold feared that Russian troops might come to the aid of the Serbs in the event of war. Before agreeing to mobilize the Austrian army, he first sent a letter of inquiry to the German government. The letter asked if help from the Germans would be forthcoming in the event of Russian intervention in a diplomatic or military struggle between Austria-Hungary and Serbia. German military and civil officials received the letter on July 5, 1914, and immediately assured the Austro-Hungarian envoy that they would support their ally (Austria-Hungary had been partners with Germany and Italy since 1888 in a defensive treaty called the Triple Alliance).

The leaders of Austria-Hungary sent a ten-point ultimatum to the Serbian government on July 23. The ultimatum stipulated (among other demands) that Austro-Hungarian officials be allowed to conduct an investigation into the assassination in Serbia and to bring to trial and punish any Serbs found guilty of involvement in Francis Ferdinand’s death. The ultimatum gave the Serbs forty-eight hours to make a satisfactory reply or face a rupture of relations with the Austrians. When the contents of the ultimatum became known, leaders of other European governments became aware for the first time that a major crisis in international affairs had arisen. European leaders seemed incapable of halting the following sequence of events even though most of them wanted to avoid the catastrophe they saw looming ahead.

The Serbs ordered mobilization of their army on receipt of the Austrian ultimatum. Nikola Pašić, Pašic, Nikola Serbian prime minister, contacted members of the Russian and French governments (allied since 1894 in the Dual Alliance) in an effort to garner support. Pašić received assurances from Czar Nicholas II of Russia that a secret agreement signed previously between Russian and Serbian officials would be honored. The agreement guaranteed Russian military assistance in any dispute between Serbia and Austria. The Serbs then sent a reply to the Austrian ultimatum on July 25.

The Serbs agreed to all Austrian demands except one: They declined to allow Austrian officials to participate in the internal Serbian investigation into any alleged plot to assassinate Ferdinand. Some historians say Pašić feared to permit Austrian participation in the inquiry because it would have revealed the complicity of the Serbian government. Other historians maintain that the Serbian rejection of the term resulted from the promise of Russian support.

The Austrians broke off diplomatic relations with the Serbs because of the unsatisfactory Serbian reply, and ordered the mobilization of their army on the Serbian border. Upon hearing of the Serbian reply and the Austrian reaction, British foreign secretary Sir Edward Grey sent an appeal to the governments of France, Germany, and Italy to convene an international conference the next day (July 26) to mediate a settlement of the crisis. Representatives of the German government declined the invitation, suggesting instead that the matter should be settled through direct negotiations between the Austrians and the Russians. Some German officials were privately urging Austrian officials to take immediate military action against the Serbs to preempt any intervention by the Russians or the French. The French general staff began recalling its Moroccan garrisons to France, a move the German general staff considered provocative. The French ambassador to Russia assured the Russian foreign affairs minister, Sergey Dmitriyevich Sazonov, of French support for whatever action the Russian government decided to take.

On July 28, the Austrian government declared war on Serbia and the Austrian army began bombarding the Serbian city of Belgrade. The next day, the German ambassador to France warned the French foreign minister that French troop movements on the German border were about to cause a German declaration of “state of imminent danger of war”—the final step before mobilization of the German military. All European diplomats understood that the mobilization of the military forces of any of the major powers meant war.

The next day, the Russian czar signed two orders for the mobilization of Russian troops, one for partial mobilization (along the Austrian border only) the other for total mobilization along Russia’s frontiers, including the border with Germany. Nicholas did not implement either order immediately. A few hours later, the German ambassador to Russia delivered a telegram from German chancellor Theobald von Bethmann Hollweg to Sazonov warning that the mobilization of Russian forces on the German border would mean war. To emphasize this point, the German emperor, William II, sent a personal telegram to his cousin, Nicholas II, warning him of the danger of war and requesting that Russian steps toward mobilization be halted. Nicholas sent a reply assuring his cousin that Russia would not mobilize.

On July 30, Sazonov joined with the Russian minister of war and the chief of the Russian general staff in implementing Nicholas’s previously signed order for full mobilization. The next day a representative of the French foreign ministry informed the Russian ambassador to France, Aleksandr Petrovich Izvolsky, that the French government had decided to go to war against Germany. At about the same time, the German government issued a declaration of “imminent danger of war.” Austrian officials simultaneously ordered mobilization of the Austrian army along its border with the Russian Empire.

British government officials failed to make clear to any of the antagonists what action they might take in the event of war between the members of the Dual and Triple Alliance systems. A few members of the French government were aware of a secret agreement contained in the Anglo-French Entente of 1904, Entente Cordiale (1904) which guaranteed that the British fleet would protect French channel ports if France became involved in a war. The British government never made public this secret protocol, nor had Parliament approved it. Nevertheless, Grey and other members of the British government talked privately throughout the crisis about British entry into the war on the side of the French.

On August 1, the French government mobilized its armed forces. The German government mobilized its own troops and declared war on Russia. German officials sent an ultimatum to the French to cease mobilization. When the French failed to comply, the Germans declared war on them the next day and delivered an ultimatum to the Belgians demanding that the German army be permitted to pass through their territory.

The Belgians rejected the German ultimatum on August 3, causing the Germans to declare war on the Belgians and invade their borders. The British government sent an ultimatum to the Germans, demanding that the German army withdraw from Belgium. When the ultimatum expired the next day, the British government declared war against the German Empire.


The war that ensued eventually involved most of the world, and the terrible loss of life attendant to that war was, sadly, only a harbinger of the carnage to come in the bloodiest century known to human history. In part owing to the damage it did to the economies of the Russian, German, and Austrian empires, World War I contributed to the success of the Bolsheviks in Russia and the rise of Nazism in Germany. In addition, the war weakened the colonial empires of Great Britain and France while bringing the United States to a newly dominant position in world affairs. The international anarchy that led to World War II can be traced directly to the impacts of World War I. World War I (1914-1918)[World War 01];outbreak

Further Reading
  • citation-type="booksimple"

    xlink:type="simple">Fay, Sidney B. The Origins of the World War. Rev. ed. 2 vols. New York: Macmillan, 1930. Argues persuasively that the actions of European governmental and military leaders, along with intellectuals and journalists, created a situation that by 1914 made a general war probable, if not inevitable.
  • citation-type="booksimple"

    xlink:type="simple">Fischer, Fritz. Germany’s Aims in the First World War. London: W. W. Norton, 1967. Asserts that the German government was to blame for the outbreak of the war.
  • citation-type="booksimple"

    xlink:type="simple">Fromkin, David. Europe’s Last Summer: Who Started the Great War in 1914? New York: Alfred A. Knopf, 2004. Asserts that diplomatic efforts to avert the war were useless, as Germany deliberately instigated hostilities for its own purposes.
  • citation-type="booksimple"

    xlink:type="simple">Joll, James. The Origins of the First World War. 2d ed. London: Longman, 2000. Presents a balanced synthesis of the enormous literature concerning the outbreak of war in 1914.
  • citation-type="booksimple"

    xlink:type="simple">Lafore, Laurence. The Long Fuse: An Interpretation of the Origins of World War I. 2d ed. Prospect Heights, Ill.: Waveland Press, 1997. Evenhanded account seeks to explain the origins of the war rather than to apportion blame.
  • citation-type="booksimple"

    xlink:type="simple">Lee, Dwight E., ed. The Outbreak of the First World War: Causes and Responsibilities. 4th ed. Lexington, Mass.: D. C. Heath, 1975. Excellent starting place for readers seeking an understanding of the events surrounding the outbreak of World War I.

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Categories: History