What happened
After the German offensive in the Low Countries and France shattered Allied defenses, the French government signed an armistice that ended organized resistance by the Third Republic.
Why it matters
The defeat of France transformed the war's balance in Europe. Germany emerged dominant on the continent, Britain was left fighting on without a major western land ally, and the conflict entered a new phase of strategic uncertainty.
Notes
This is the clearest marker for the Axis high-water point in western Europe.