Western Europe · United Kingdom and France vs Germany
Britain and France declare war
3 September 1939
After Germany ignored ultimatums to withdraw from Poland, Britain declared war at 11:00 on 3 September 1939 and France followed at 17:00. Australia, New Zealand and India declared the same day; South Africa followed on 6 September and Canada on 10 September.
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Day by day
Chamberlain broadcasts at 11:15 that Britain is at war; the liner Athenia is torpedoed by U-30 that evening.