Of Austria (June 28th 1914) No, it's not going to mean much to most of us. I mean it happened a 100 years ago halfway around the world... so what's the big deal? At the time, it was recognized as a tragedy, especially in Austria, but know one would have guessed that the assassination would be directly and indirectly affecting events 100 years later. The Reader's Digest version of this is that Austria held Serbia (the country where the Archduke was murdered) responsible for the attack, and made demands on Serbia which they couldn't comply with. Austria declared war on Serbia. Russia who was an ally of Serbia, declared war on Austria-Hungary. Germany, who was an ally of Austria-Hungary declared war on Serbia and Russia. And that's how WWI began. Countries began taking sides against one another over this one event. At the time WWI was considered to be the war to end all wars. At the conclusion of the war, the allies (especially France) saw fit to punish Germany severely... maybe too severely. You see the other "shoe" that dropped that helped trigger WWI was the Franco-Prussian War of 1870, which left France battered and seeking revenge, which would happen almost 50 years later. As we now know there was a corporal in the German army during WWI, who was able to use the weakened state of post-war Germany to build a power-base in which to start WWII. The results of WWII helped initiate the Cold War. One of the things I find most fascinating is the change that occurred in mid-Europe and the middle-East due to the what happened in WWI... Not only did WWI end the Austria-Hungary empire, it also ended that of the Ottoman's, which affected and is still affecting the Middle East. So while June 28th may not mean much to most... It's certainly one of the most important dates in the history of the planet.