World War I erupted in 1914, but there were many things leading up to this. Some of the reasons this horrible war started are militarism, alliances, and nationalism. These were some of the main reasons this war started.

Militarism describes when a nation would have a prepared military to fight at any time. Militarism is the belief in being prepared at all times. There were many reasons everyone was so ready to fight. One of those reasons was that alliances of nations did not trust alliances of other states. Technology was also developing rapidly. New weapons were being developed that helped to escalate the military build-up. An example is the Maxim Gun.

Alliances were groups of nations that had treaties with each other. Two of the big alliances are the Allied Forces and the Central Powers; they were basically against each other. The Allied Forces consisted of the United...