Germany was blamed for the start of World War I.
Germany and Austria-Hungary were in an alliance called the Triple Alliance. There were many factors that put Europe on the verge of exploding by 1914. Imperialism, militarism, nationalism, and entangling alliances were a few of these causes. However, when a group of Serbians assassinated Franz Ferdinand, who would have been the next king of Austria-Hungary, Austria-Hungary wanted to make Serbia pay for this assassination. The government of Austria-Hungary made a series of demands for the Serbian government to meet. While the Serbian government tried to meet these demands, they weren’t able to meet them all. Thus, Austria-Hungary wanted to go to war.
Austria-Hungary was convinced the Soviet Union would come to the aid of their long time friend, Serbia, if war was declared. Thus, before declaring war, Austria-Hungary asked Germany if Germany would support Austria-Hungary if they declared war on Serbia. Germany agreed to do this. The Allied leaders believed Germany could have prevented Austria-Hungary from declaring war by refusing to support Austria-Hungary if Austria-Hungary decided to declare war on Serbia. Since Germany agreed to support Austria-Hungary if they declared war on Serbia, the Allied leaders blamed Germany for the start of the war. The Germans resented this greatly since they believed Austria-Hungary started the war. However, the Allies saw things differently and blamed Germany for failing to take action that could have prevented World War I from starting at this time.