On June 28th, 1914, the Serbian assassination of the Crown Prince Franz Ferdinand of Austria was the match that lite the fuse which was already in place.
World War I began on July 28th when Austro-Hungarian Empire declared war on Serbia and proceeded to bombard Belgrade on July 29th. The Germans, had already pledged their support to Austria-Hungary Empire and on August 3rd Germany declared war on France.
Germany's Schlieffen Plan was put into operation when the German Army invaded Luxembourg and Belgium. Germany's military goal was the defeat of France and the Lowlands, .
The Germans point of view was of a country that had never lost a major conflict. The German people went to war expecting to win because they knew of nothing else and they lost, but did not learn their lesson resulting in the 2nd World War.
Germans and Austrians are one of a kind. Recall that German voters gave a majority to a fanatical Austrian Nazi in 1933?
I really hope you guys are not going to state the Germans did not start World War II in Europe in 1939?