Lasting from 1914 to 1918, World War 1 claimed over 16 million lives, bolstered military technology, and brought world powers to the European theater to fight till ultimate destruction. Who can be blamed for the carnage seen throughout this conflict?
Both Austria-Hungary and Germany are responsible
By giving support via a blank check and having such a strong allyship between them, both Austria-Hungary and Germany had the motive and means to instigate a worldly conflict.
Austria-Hungary and Germany saw an opportunity to conquer and took it
Austria-Hungary was waiting for an opportunity to assert their influence and their allyship with Germany guaranteed them a "blank check," assuring Germany's support and resources to Austria-Hungary's prerogative.
With aggressive foreign policy and ulterior motives, Germany is guilty of the war outbreak by bolstering tensions and whispering in the ears of their allies.
Germany coerced their ally, Austria-Hungary, to begin conflict
Without the coercion from Germany, Austria never would have gone through with retaliation following the Assassination. As the only war to have been caused by assassination, Germany was certainly whispering to provoke an overreaction.
Along with 'Weltpolitik' foreign policy of colonial expansion and previous rivalries, Germany's aggressive presence on the world stage greatly bolstered tensions between actors going into World War 1.
The Black Hand Serbian Society and the Bosnians are responsible
The tensions completely imploded with the assassination of a prominent Austrian by Serbian Nationalists. Without the rise of Serb nationalism, World War 1 would not have broken out.
Increased Serbian Nationalism led to the incitement of conflict
As a region consistently occupied by outer forces, Serbian nationalism in the Balkans peaked in the days before World War 1, and the Assassination of Archduke Ferdinand, which ultimately resulted in the spiraling conflict was World War 1.
Considering the interconnectedness of allyship, rising global tensions, and widespread imperialism, all actors must bear some responsibility for the outbreak of World War 1.
European expansionism led to the outbreak
Imperialistic and nationalistic feelings were widespread as nations scrambled to claim their pieces of unclaimed territories. Due to the scramble for colonies, tensions arose between the European powers, who viewed the amount of land as direct indicators of world power.
Conflicts over alliances dragged all powers in, creating a global conflict
A great majority of world leaders at the time were related, and more notably, their nations were all intertwined through a system of tight treaties and agreements in which actors would fearlessly support those they had agreed to flank in conflict.