What caused the First World War?

--Did the alliance Alliance System make war more likely or less likely? The Alliance System between the European countries divided the continent into two rival groups. In 1817, Germany gained control over the region of Alsace-Lorraine as a prize for wining the Franco-Prussian War. Otto von Bismarck, the German chancellor, knew that one day, France would regain the land by getting help from the other countries. In order to prevent this, he made alliances with the …

…other countries to get involved, building the attack to the first World War. It was not until 1918, when the WWI finally showed its end. --What caused the First World War? The nationalism of each country, competitions in the military and imperialism, and the alliance system gradually built the tension of the world war. The assassination of Ferdinand was what allowed a conflict to break out, which was developed in to WWI by the domino effect.