What caused WWI Throughout World War I, in 1914 many countries were focused in having an alliance, as the alliances were spreading around the world, It was mostly showing that many other countries had a universal perspective. Also the outgrow of armament was one main phase and trying to race on who has the largest army. But as well the WWI had made aforementioned item to be included with imperialism, militarism, and nationalism. Before WWI was triggered, an excessive number of defence alliances existed between only the major European countries. There are several reason why countries just wanted allies because as they gather more power they will be able to the land and rule over a country, that leads them to imperialism. As they british