why did britain declare war on germany in ww2
England and France, bound by treaty to defend Poland, called on Germany to withdraw. When Germany did not, England and France declared war on Germany on September 3, 1939. At this point, Russia was not at war, and there was no reason to declare war on Russia.England and France, having declared war, did absolutely nothing to help Poland, and Germany proceeded to demolish Poland.On September 17, 1939, pursuant to a secret protocol in the treaty, Russia invaded Poland from the East. don't really see how Poland would have been helped by Britain and France declaring an unwinnable war. To be in a position to declare war on the Soviets, the Allies would have to get through Germany first. As things turned out, the Germans went through France instead.