The long term causes of World War I can be identified using the acronym MAIN:
Militarism: Tensions arose between countries due to competition. The Germans and British rapidly became involved in a naval race, each nation attempting to control the seas. Neither of the countries wanted to have its naval supremacy undermined and tried to outdo each other.
Militarism: Tensions arose between countries due to competition. The Germans and British rapidly became involved in a naval race, each nation attempting to control the seas. Neither of the countries wanted to have its naval supremacy undermined and tried to outdo each other.
Alliances: The Triple of Alliance (Central Powers) was formed by Italy, Germany, and Austria-Hungary in the late nineteenth century. The Italians and Germans entered the alliance seeking protection against the French, whereas Austria-Hungary entered as it gave them the freedom to pursue politics in the Balkans, safe from the Russians. To combat this new creation, the Triple Entente (Allies) was divised between Britain, France, and Russia. This caused strained relations and the development of war plans.
Imperialism: Countries competed to colonize the globe in order to gain an upper hand in the world economy. Imperialist powers fought each other for much-desired lands (e.g. Britain and Russia in Persia). Competition grew especially tense between Britain and Germany and France and Germany. Only international conferences prevented all-out war as diplomatic relations stretched taut.
Nationalism: Over time, nationalist revolutions and independence movements created new countries, stripping others of their colonial possessions. Imperialist powers supported these rebellions to spite and weaken their rivals. For example, Russia supported Pan-Slavism, a movement geared towards the political unification of the Slavs in Austria-Hungarian lands. As a result, Austria-Hungary would be vastly weakened. Austria-Hungary and its ally, Germany, attempted to counter this motion. This provided a nice background for future conflict.