Top 5 Causes of WWI

1. Asassination: There were several causes of World War I. The most immediate cause was the assassination of Archduke Francis Ferdinand of Austria-Hungary. Austria-Hungary decided that Serbia was to blame for the assassination and declared war on Serbia.
2. Nationalism: Before the assassination, there were other things going on in Europe that led up to the war. One thing was an increase in the feeling of nationalism in many European countries. Nationalism is something like patriotism, so you may be surprised to hear that it was one cause of the war, but nationalism doesn't just mean supporting your own country. Nationalism means putting the interests of your own country above everything else and ignoring the rights of people in other countries.
3. Alliances: When the assasination happend the two countries who began to fight and invade had treaties with other countries that if they were to be invaded that they would come to their aid. These alliances starteed a domino effect because the two countries that had alliances also had other alliances and when they got invaded even more countries joined the war.
4. Militarism: All the countries involved in the problems were building large armies and navies pre-war. A class of professional and powerful military officers developed and began to dominate civil authorities. Also before the conflict happened, the militaries of each country had drawn up complete plans for mobilization. The existence of secret battle plans pussed spying, which caused greater hatred and fear between the rival countries.
5. Imperialism: Another factor which contributed to the increase in rivalry in Europe was imperialism. Great Britain, Germany and France needed foreign markets after the increase in manufacturing caused by the Industrial Revolution. These countries competed for economic growth in Africa. Although Britain and France resolved their differences in Africa, several problems before the war involved te fighting between France and Britain against Germany in North Africa. The Ottoman Empire was looking to invade Austria-Hungary, the Balkans and Russia.