Germany Invades Belgium Through the Schlieffen Plan
A German war plan meant to knock out France in six weeks instead drags Britain into the war on the first day.
Quick facts
- Plan's author
- Alfred von Schlieffen, German Chief of Staff
- Route
- Through Belgium and Luxembourg
- Britain enters war
- 4 August 1914
What happened
Facing a war on two fronts against France and Russia, German chief of staff Alfred von Schlieffen had devised a plan years earlier to focus almost all of Germany's resources on a fast, decisive battle in the west before Russia could fully mobilize in the east. Schlieffen settled on a wide flanking march through Belgium and Luxembourg to avoid France's heavily fortified eastern border, aiming to encircle and destroy the French army quickly. His successor, Helmuth von Moltke, modified the plan before 1914. When Germany invaded Belgium on 4 August to execute it, German forces smashed through Belgian defenses and appeared, for a time, close to victory.
Why it matters
Violating Belgian neutrality, which Britain had guaranteed by treaty, brought the British Empire into the war on the day of the invasion. It also forced Germany to fight the exact two-front war Schlieffen had designed the plan to avoid, once the quick western victory failed to materialize.
How we know
Imperial War Museums lays out Schlieffen's original strategy and Moltke's changes to it, drawing on the German General Staff's own prewar planning documents as reconstructed by postwar historians.
Sources
- Imperial War Museums. The Schlieffen Plan · Reputable sourceiwm.org.uk · The domain "iwm.org.uk" is on our Reputable source registry. · Link is live and its text matches the event's key terms (Jul 2026)
- World History Encyclopedia. Schlieffen Plan: Germany's WWI Plan to Invade France · Reputable sourceworldhistory.org · The domain "worldhistory.org" is on our Reputable source registry. · Link is live and its text matches the event's key terms (Jul 2026)
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