Britain Pledges Poland: War With Germany Looms
Britain and Poland signed a mutual defense agreement on August 25, 1939, formalizing a guarantee that Neville Chamberlain had made in March after Germany absorbed the rest of Czechoslovakia. The pact committed Britain to military action if Poland were attacked by a "European power," a transparent reference to Germany. Hitler had been planning to invade Poland on August 26 but delayed the attack by five days after learning of the Anglo-Polish pact, hoping to negotiate Britain out of its commitment. He failed. Germany invaded Poland on September 1. Britain declared war on September 3, honoring the guarantee. The pact drew Britain into World War II on a firm legal obligation rather than the ambiguous moral arguments of 1914.
August 25, 1939
87 years ago
Key Figures & Places
What Else Happened on August 25
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