One cause of WWI is the assassination of Archduke, Franz Ferdinand of Austria-Hungary and his wife on June 28, 1914 by a Serbian nationalist from the Black Hand organization. Immediately this event is the trigger that set off declarations of the war. In response to the assassination of Ferdinand, Austria-Hungary declared war on Serbia. Austria blamed Serbia for the assassination since Serbia supported the Black Hand’s in order to be free of Austria’s rule. Due to Austria’s alliance with Germany, Serbia tried to get help from Russia. When Russia began to mobilize in result of its alliance with Serbia, Germany declared war on Russia on August 1, 1914. Two days later Germany declared war on France. Germany swept through Belgium on its way to France, the invasion of Belgium caused Britain to declare war on Germany.