On June 28, 1914, Archduke Franz Ferdinand went on a tour in Sarajevo, Bosnia where people in the town was waiting to see him. This wife was also with him. We was almost murdered before this too.
In the crowd there was a couple of members of the black hand gang. They want to kill Archduke Franz Ferdinand because they didn't agree with his decisions.
One of the members of the black hand gang tried to kill him with an explosive but failed to do.
One of the members from the Black hand gang, Gavrilo Princip, wasn't happy that Archduke didn't die from that so he had to do it himself.
Gavrilo Princip ran up to Archduke and his wife and shot them while in the car in front of a crowd. Shooting them that close killed both of them.
The killing of Archduke started ww1. Austira decalred war on Serbia on July 28, 1914.