What event triggered a diplomatic crisis that led to the onset of World War I?

The assassination of Archduke Franz Ferdinand is recognized as the catalyst for a series of events that ultimately led to the outbreak of World War I. On June 28, 1914, Ferdinand, the heir to the Austro-Hungarian throne, was shot and killed by Gavrilo Princip, a member of a nationalist group seeking to liberate South Slavic peoples from Austro-Hungarian rule.

This assassination set off a diplomatic crisis, as Austria-Hungary, with the backing of Germany, perceived it as a direct challenge to its authority and sovereignty. The July Ultimatum was sent to Serbia, where the assassin had ties, demanding various concessions. Serbia’s response did not satisfy Austria-Hungary, leading to the declaration of war on July 28, 1914.

This escalated swiftly, involving alliances and treaties, as other nations were drawn in. Russia mobilized to support Serbia, leading Germany to declare war on Russia, followed by declarations against France and Belgium, further expanding the conflict and drawing in nations across Europe. Thus, the assassination is crucial to understanding how the intricate web of alliances, national interests, and rising tensions resulted in a full-scale global war.

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