The most prominent factors which led to World War 1 were nationalism, militarism, imperialism, the Balkan and Morocco crises, and the alliance system. As luck would have it, these factors either started in response to, or because of each other. The alliance system was one of the last factors to emerge before the war. The alliance system was a main cause of World War 1; it came into play because of a few factors, and did not cause the war alone.
Nationalism, the love and support of one's country, has always existed. During this time, nonetheless, it took part in the culmination of one of the most famous wars in history. As so much pride was devoted to countries, it made the potential for peace between past rivals less likely. It also meant that most nations, particularly the great powers, would rather fight a war than back down from a rival's diplomacy.
Since no country felt easy about fighting in a war alone, nationalism was a contributing factor to the alliance system. Allies provided a lot of ease with the growing militaries in almost every country.
Militarism, a policy of aggressive military preparedness, in this period of time gave all countries great reason to feel the heavy weight of a looming war. Great Britain had a naval policy to have the largest military force hands down. That, along with the predominate feeling of war, provided countries with a strong reason to create an incredibly strong military force. This led to an arms race, which made the impending war seem certain. The military planning in some countries also caused an increased fear of war. Military machines were being developed; each country was appointing a staff of experts. The greatest problem with this was the fear that the expert would precipitate...