The trigger of the First World War was the assassination of Archduke Francis Ferdinand, heir to the Austro-Hungarian throne, committed in 1914 in Sarajevo by a nationalist student. But this fact was only the match that lit the powder. In fact the conflict was the result of competition between the major European powers to extend their colonial rule and achieve the international supremacy. These countries were already engaged for several years in an accelerated arms race. The main contenders were, first, the Allied nations: Britain, France and Russia, and, on the other, the Central Powers, ie Germany, Austria-Hungary and Turkey. Were gradually adding other contenders, like the U.S., Italy and Japan, who supported the allied nations, or Bulgaria, which sided with the Central Powers. It was a bloody war that killed millions of soldiers and civilians in the western and eastern fronts. The conflict ended in 1918 with the Allied victory, as enshrined in agreements signed in the Versailles conference which began on January 18, 1919.
It is estimated that were approximately eight million, many disappeared and about six million people were left disabled.