1914: The Year the World Went to War

1914 didn't just start a war—it ended the "long 19th century" and birthed the modern geopolitical order. The cascade from Sarajevo assassination to global conflict unfolded with grim inevitability.

The Spark: June 28

Archduke Franz Ferdinand, Austro-Hungarian heir, assassinated in Sarajevo by Gavrilo Princip (Bosnian Serb, Black Hand-linked). Vienna saw existential threat to multiethnic empire.

The Fuse: July Crisis

• July 23: Austria-Hungary issues 48-hour ultimatum to Serbia (designed for rejection).
• July 28: A-H declares war on Serbia. Russia begins mobilization (supporting Slavic Serbia).
• July 29-30: Partial → full Russian mobilization. Germany demands halt.

The Explosion: August

• Aug 1: Germany declares war on Russia; invades Luxembourg.
• Aug 2: Germany ultimatum to Belgium (free passage). France mobilizes.
• Aug 3: Germany declares war on France; invades Belgium (Schlieffen Plan).
• Aug 4: UK declares war on Germany (Belgian neutrality + Entente).
• Aug 6: Austria-Hungary declares war on Russia.
• Aug 12: UK/France declare war on Austria-Hungary.
• Aug 23: Japan enters (Anglo-Japanese Alliance) — seizes German Pacific colonies.

Why It Spread So Fast

Rigid mobilization plans (especially Schlieffen) treated delay as defeat. Alliance chains (Triple Entente vs. Triple Alliance) turned bilateral into continental. Imperial reach made it global instantly—colonial troops, naval stations, resource flows.

By December 1914

Western Front: trench stalemate (Marne, Ypres). Eastern Front: fluid, huge casualties (Tannenberg, Galicia). Global: Africa, Pacific, Middle East, naval war. 5M+ mobilized; ~1M dead already. No end in sight.

1914 didn't just start WWI. It started the 20th century.