The July Crisis of 1914: How Five Weeks Led Europe to War

Between June 28 and August 4, 1914, Europe went from a royal assassination in a provincial capital to a war among all its great powers. Historians call those five weeks the July Crisis. In the words of Annika Mombauer, writing for the International Encyclopedia of the First World War, published by the Freie Universität Berlin, explaining how it happened has "divided historians for over a hundred years and continues to be controversial."

The puzzle is not why Europe was tense. It was. The puzzle is why this crisis, unlike several before it, ended in war. This deep dive walks through the decisions of those weeks in order, quotes the key documents, and then sets out the long argument over responsibility, including where today's historians agree and where they still do not.

A Europe practiced at avoiding war

It is easy, with hindsight, to see 1914 as inevitable. Mombauer cautions against that. Every great power government feared that a major European war would come at some point, and that fatalism shaped their choices. But the last years of peace also saw what historians have called "avoided wars": crises settled by conferences and mediation rather than fighting. Alliances, she notes, can be argued to have "generally functioned as a restraint on war" rather than a cause of it.

That background matters. In July 1914, some governments again reached for diplomacy. In Vienna and Berlin, in Mombauer's account, there was no such desire for another conference.

Sarajevo, June 28

On Sunday, June 28, 1914, Archduke Franz Ferdinand, heir to the Austro-Hungarian throne, and his wife Sophie visited Sarajevo, the capital of Bosnia, which Austria-Hungary had annexed in 1908. Six young conspirators waited along the announced route.

Their links ran to Belgrade. Mombauer describes how three of them, including the nineteen-year-old Bosnian Serb Gavrilo Princip, had moved to Belgrade and fallen under the influence of underground nationalist groups such as the Black Hand, officially "Union or Death," an officers' organization whose members included Dragutin Dimitrijević, known as Apis, the head of Serbian military intelligence. The conspirators were trained in Belgrade and armed from the Serbian state arsenal at Kragujevac. Mombauer is careful on one point: this was "not, however, a plot which had been sanctioned by the Serbian government."

The first attempt failed when Nedeljko Čabrinović's bomb bounced off the archduke's car. Later, after a change of route that apparently was not passed on to the lead driver, the archduke's car stopped in front of Princip, who shot Franz Ferdinand and Sophie. Both died.

There was an irony here that Mombauer underlines. Franz Ferdinand had opposed war with Serbia and had clashed with the chief of the general staff, Franz Conrad von Hötzendorf, over the issue.

Vienna and Berlin decide

In Vienna, the murder was immediately seen as a Serbian provocation, even though hard evidence was scarce. Conrad, who had long wanted a reckoning with Serbia, demanded mobilization the day after the assassination. Foreign Minister Leopold von Berchtold was more cautious but agreed it was an opportune moment "for solving the Serbian question."

First, Vienna needed to know what Germany would do. When the German ambassador, Heinrich von Tschirschky, reported that he was counseling restraint, Kaiser Wilhelm II scribbled in the margin, as Mombauer quotes him: "The Serbs must be sorted, and that right soon!"

On July 5, the Austrian envoy Count Alexander von Hoyos arrived in Berlin. He was assured that Germany would support Austria-Hungary unconditionally, even if war with Serbia became a European war. This promise is known as the "blank cheque." Historians have debated why Berlin gave it, and some see it as a crucial step toward war; Mombauer cites Dominic Lieven calling it "the single most decisive moment in Europe's descent into war."

Why would Berlin take that risk? Mombauer explains that German leaders feared Russia's growing army and railways would soon make it impossible to fight a successful war, and saw the crisis as a chance to test, and perhaps break, the Entente. Chancellor Theobald von Bethmann Hollweg summed it up: if war did not come, "we still have the chance to break the Entente apart over this."

On July 7, Austria-Hungary's joint council of ministers agreed to provoke a war with an ultimatum, so that Vienna would appear to be acting reasonably. Only the Hungarian prime minister, István Tisza, dissented. The ultimatum was then delayed, partly because soldiers were on harvest leave and partly to time its delivery for when French President Raymond Poincaré had left Russia after a state visit, so that the two allies could not easily coordinate. Its text was settled on July 14 and was meant to be unacceptable.

The ultimatum and the Serbian reply

At 6 p.m. on July 23, the Austro-Hungarian minister in Belgrade delivered the note. The English translation held by Brigham Young University's World War I Document Archive shows that Serbia was required to suppress anti-Habsburg publications and organizations, dismiss officers and officials whose names Vienna would supply, and, in points five and six, accept the participation of "the organs of the Imperial and Royal Government" in suppressing subversion and in a judicial inquiry on Serbian soil. The answer was due "by Saturday, the twenty-fifth instant, at 6 p.m., at the latest."

The minister's private instructions, in Mombauer's account, removed any doubt: "However the Serbs react to the ultimatum, you must break off relations and it must come to war."

Serbia's reply surprised everyone. On paper it accepted almost all the demands. It drew the line at Austro-Hungarian officials taking part in the investigation, which, in the reply's words, "cannot be accepted, as this is a violation of the constitution and of criminal procedure." Christopher Clark has called the reply a "masterpiece of diplomatic equivocation," and Mombauer cites Thomas Otte's judgment that no answer would have been enough because "Vienna wanted war." Even Wilhelm II thought the reply removed every reason for war. Britain's foreign secretary, Sir Edward Grey, proposed mediation, but Berlin gave it only half-hearted support and Vienna did not take it up.

From a local war to a general war

Russia reacted first among the Entente powers. Foreign Minister Sergei Sazonov judged war "unavoidable" on reading the ultimatum. Russia advised Serbia not to resist an invasion, asked Vienna to extend the deadline, and, on July 25, decided on partial mobilization, called the "period preparatory to war," which took effect the next day. Historians who place responsibility on Russia make much of this step. Mombauer's view is more measured: it did not make war unavoidable, though, in a phrase she quotes, it was "the first Russian move down the slippery slope."

France was caught between reassuring Russia and keeping Britain on side. Poincaré and the Russians had agreed on "an intransigent opposition to any Austrian measure against Serbia." Britain refused to commit either way. Mombauer notes the argument that an early British declaration might have restrained Berlin, but she judges it unfair to treat Grey's ambiguity as a cause of the war, since a divided cabinet and public would not back war until the German invasion of Belgium.

Austria-Hungary declared war on Serbia on July 28 and immediately bombarded Belgrade. Nicholas II, according to Siobhan Peeling's entry on the tsar, hesitantly ordered general mobilization on July 30. By August 1, Germany was at war with Russia. Germany's war plan, known as the Schlieffen Plan, required moving west through Luxembourg, invaded on August 2, and Belgium, invaded on August 4. That same day, Britain declared war on Germany. Italy stayed neutral.

The long argument over responsibility

The argument began before the shooting did. Mombauer notes that even during the crisis, every government tried to appear as the attacked party, since none could rally volunteers for a war of aggression.

In 1919, the victors wrote into the Treaty of Versailles Article 231, in which Germany accepted "the responsibility of Germany and her allies for causing all the loss and damage" suffered by the Allies. Historians still disagree about what that clause claimed. Jay Winter describes it as an Allied claim that Germany "bore sole responsibility for the outbreak of the war." Alan Sharp, in the same encyclopedia, argues that German nationalists exploited an interpretation of exclusive responsibility for the war, "which Article 231 did not assert."

Winter traces how the debate unfolded in generations. In the first generation of writing, which Winter dates from 1914 to 1939, many historians wrote in their nations' defense. The French historian Pierre Renouvin and the Italian Luigi Albertini concluded that the war was planned in Vienna and Berlin, while the American revisionist Harry Barnes argued in 1927 that Serbia, Russia, and France bore principal responsibility. In the 1960s, the German historian Fritz Fischer used archival evidence to emphasize the aggressive character of German policy, setting off a fierce controversy.

More recently, Christopher Clark's 2012 book The Sleepwalkers took an international approach that, as Mombauer puts it, "largely exonerates Germany." Clark wrote that there is no smoking gun, "or, rather, there is one in the hands of every major character." Others have disagreed: Mombauer quotes Richard Hamilton and Holger Herwig's 2003 judgment that the idea of an innocent "slide" into war "stands sharply opposed to the evidence now available."

Where does that leave a reader? Mombauer's own conclusion is that there is still no consensus, and that one can build a case assigning some responsibility to every major power. But if all leaders bore responsibility, she argues, "arguably they were not equally so": in Vienna and Berlin, decision-makers deliberately used the assassination as the trigger for a war they believed unavoidable in the long run, while St. Petersburg, Paris, and London reacted to that provocation. Readers will find other serious historians weighting the evidence differently, which is exactly why the July Crisis remains such a rich subject.

Key takeaways

• The July Crisis ran from the Sarajevo assassination on June 28, 1914, to Britain's declaration of war on August 4.
• The assassins had ties to a Serbian officers' network, but the plot was not sanctioned by the Serbian government.
• Germany's "blank cheque" of July 5 and Austria-Hungary's deliberately harsh ultimatum of July 23 turned a crime into a crisis.
• Russian mobilization, French support for Russia, British ambiguity, and Germany's war plan widened a Balkan war into a European one.
• Historians have argued about responsibility since 1919 and still have not reached a consensus, though many emphasize decisions made in Vienna and Berlin.

Sources

• Annika Mombauer, July Crisis 1914, International Encyclopedia of the First World War, Freie Universität Berlin (version 1.1, September 20, 2018)
• Jay Winter, Historiography 1918–Today, International Encyclopedia of the First World War, Freie Universität Berlin (2014)
• Alan Sharp, The Paris Peace Conference and its Consequences, International Encyclopedia of the First World War, Freie Universität Berlin (version 1.2, March 17, 2026)
• Siobhan Peeling, Nicholas II, Emperor of Russia, International Encyclopedia of the First World War, Freie Universität Berlin (2014)
• Brigham Young University, World War I Document Archive, The Austro-Hungarian Ultimatum to Serbia (English translation)
• Brigham Young University, World War I Document Archive, The Serbian Response to the Austro-Hungarian Ultimatum (English translation)
• Yale Law School, The Avalon Project, Treaty of Versailles, Part VIII: Reparation (1919)