On 23rd August 1939, Vyacheslav Molotov and Joachim von Ribbentrop – the Soviet foreign minister and the German foreign minister – signed the Treaty of Non-aggression between Germany and the Union of Soviet Socialist Republics, otherwise known as the Nazi-Soviet Pact. Outwardly it was a guarantee that neither side would fight against the other in war, but a ‘secret protocol’ also outlined how Eastern Europe would be divided between the two countries. This agreement cleared the way for the Nazi invasion of Poland just nine days later.
Stalin’s Communist USSR distrusted Hitler’s Nazi Germany, knowing that ultimately Hitler intended to invade and annex Russia. Similarly, Britain distrusted Stalin due a fear of Communism. Although talks took place between Britain and Russia in early August 1939 regarding a possible alliance against Hitler, they were never taken seriously by the British government who sent their representative by a slow boat and gave him no authority to actually make any decisions.
Frustrated, Stalin’s government received Ribbentrop later that month. He proposed the Nazi-Soviet agreement which, in the face of continued British reluctance to form an alliance, was accepted. The Soviet government almost certainly knew that Hitler would break the non-aggression pact at some point and would invade Russia, but at least the pact delayed that and gave time to prepare.
The Nazi-Soviet Pact was broken less than two years after it was signed, when Nazi forces invaded the Soviet Union in Operation Barbarossa on the 22nd June 1941. All the territory gained by Russia under terms of the ‘secret protocol’ was lost in just a matter of weeks.