How did the death of archduke Franz Ferdinand help the collapse of peace in Europe?

The assassination of Archduke Franz Ferdinand of Austria-Hungary in June 1914 ignited existing tensions among European powers, leading to the outbreak of World War I. His death set off a chain reaction of alliances and mobilizations, as countries like Germany, Russia, and France were drawn into conflict due to their commitments to support their allies. This event shattered the fragile peace maintained by diplomatic agreements and intensified nationalist and militaristic sentiments across Europe, ultimately resulting in a devastating war.