The Main Instigator of World War I refers to the series of interconnected events, alliances, and political tensions that ultimately led to the outbreak of the conflict in 1914. While many nations played a role, the assassination of Archduke Franz Ferdinand of Austria-Hungary is often cited as the immediate catalyst, setting off a chain reaction among the major powers. This term encapsulates the complex web of nationalism, militarism, imperialism, and alliances that contributed to the war's ignition.