The World War I occurred because of two major factors, nationalism and imperialism. Some countries in Europe had lot of colonies around the world (lik France, the British Empire), while some didn't, or had only few (like Germany, Austria-Hungary). The countries that didn't had lot of colonies had big imperialist aspirations, and they wanted much more colonies for them in order to be able to have much more natural resources at disposal, as well as spheres of influence. This was not fondly seen by the countries that already had lot of colonies, as that meant that they will have to give up from some of them. This resulted in big dispute and lot of tensions, and eventually those tensions led to the World War I, the worst things that has happened to the humanity until then.
