WORLD HISTORY

Detailed explanation-1: -German troops invaded Poland on September 1, 1939, triggering World War II. In response to German aggression, Great Britain and France declared war on Nazi Germany.

Detailed explanation-2: -Honoring their guarantee of Poland’s borders, Great Britain and France declare war on Germany. Two days earlier, on September 1, 1939, Germany had invaded Poland.

Detailed explanation-3: -When Britain declared war on Germany on 3 September 1939 it did so for only one reason-Germany had invaded Poland, and Britain had guaranteed to support her ally, like it had supported Belgium in WW1. The diplomat and writer Sir Nicholas Henderson, himself a former ambassador to Poland, called it “a fatal guarantee".

Detailed explanation-4: -France and Britain refrained from a critical reaction to the Soviet invasion and annexation of Eastern Poland since neither country expected or wanted a confrontation with the Soviet Union at that time.

Detailed explanation-5: -On 3 September 1939-two days after the German invasion of Poland-France declared war on Nazi Germany according to its defensive treaty with Poland, when France’s ultimatum to Germany, issued the previous day, expired at 17:00.