How did the assassination of Archduke Franz Ferdinand help cause World War One?
Archduke Franz Ferdinand was assassinated by a Bosnian Serb nationalist on June 28 1914. In retaliation, Austria-Hungary declared war on Serbia and bombed Belgrade on July 28 1914. Russia and France, who had mutual support treaties with Serbia mobilised their forces. Germany, which had a mutual support treaty with Austria-Hungary declared war on Russia, and then violated the neutrality of Belgium by invading Belgium in order to attack France bypassing the strong defensive positions the French had installed on the French/German Border. As a consequence of the invasion of Belgium, Britain declared war on Germany on August 4 (although it may have done so anyway given its treaty commitments to France and Russia). In 7 days, a retaliatory strike by Austria-Hungary on Serbia purportedly over the assassination had escalated into a full scale war with Austria-Hungary and Germany on one side against Serbia, Russia, France, Belgium and Britain on the other.
