The influence of nationalism, imperialism, militarism and alliances on Great Power rivalry by the end of the 19th century

The assassination of the Archduke Franz Ferdinand and his wife was critical in setting off the chain of events that led to the First World War. Not only was it a bad day for the Archduke and his family, but also a bad day for Europe. Archduke Franz Ferdinand was heir to the throne of Austria-Hungary. He was inspecting the army in Sarajevo with his wife Sophie. The royal couple arrived by train at 9.28am. Seven young Bosnian Serbs planned to assassinate Franz Ferdinand as he drove along the main road in Sarajevo, the Appel Quay. The first conspirator who tried to kill Franz Ferdinand threw a bomb at his car. He missed and was arrested. The Archduke escaped unhurt. He decided to abandon the visit and return home via a different route to the one planned. No one had told the driver the route had changed. On the way back, therefore, the driver turned into Franz Josef Street, following the published route and, when told of his error, stopped the car to turn around. Unfortunately, the car stopped in front of Gavrilo Princip, one of the conspirators, who was on his way home thinking he had failed. Princip pulled out a gun and shot at Franz Ferdinand, hitting him in the jugular vein. There was a tussle, during which Princip shot and killed Sophie. By 11.30am, Franz Ferdinand had bled to death. It caused the war because Austria blamed Serbia for the killing of the Archduke Franz Ferdinand. Then Austria declared war on Serbia, the Russian army got ready to help Serbia defend itself against the attack and Germany sends a demand to Russia ordering it to hold back from helping Serbia. Then Germany declared war on Russia. The French army is put on a war footing getting ready to fight a German invasion. After all of that Germany declares war on France and invades Belgium, Britain orders Germany to withdraw from Belgium and the Germans did not listen. As you can see the assassination of the Archduke Franz Ferdinand was the cause of different events which then led to the war indirectly.

I think the most significant cause of World War one was the assassination of the Archduke Franz Ferdinand

arresting and exicuting citizens

a.   it resulted in widespread unemployment.