the invasion of Poland started on the 1st of September 1939 which marked the beginning of World War 2 from the West the German invasion began one week after the signing of the Molotov Ribbentrop pact between Germany and the Soviet Union the Soviets invaded Poland from the east on the 17th of September the campaign ended on the 6th of October with Germany and the Soviet Union dividing and annexing the whole of Poland.
under the terms of the German Soviet frontier treaty at the beginning of World War 2 although they were slow in actually attacking Germany Great Britain and France did declare war against it after Germany marched with its troops into polish territory the reason for this was the treaty where they guaranteed Poland against foreign invasion however the USSR also invaded eastern Poland after two weeks but neither France nor the United Kingdom declared war.
on the Soviets because there was no declaration of war issued by Britain and France against the Soviet Union or any direct help for Poland led many Polish people to believe that they had been betrayed by their Western allies who guaranteed their borders the question of today’s video why did Britain and France not declare war on the Soviet Union when the Red Army invaded Poland.
a political alliance was signed between France and Poland on February 1921 in the background of the negotiations that ended the polish-soviet war by the Treaty of Riga France wanted to protect the new countries that emerged after the first world war even though this protection was done more through diplomacy the agreement assumed a common foreign policy bilateral economic contacts and even assistance.
in case one of them became a victim of an unprovoked attack hence this was a defensive alliance between the two countries a new alliance started to be formed in 1939 the convention was signed on may 19th 1939 in the French capital this was a military convention a link between the armies and was not enforced legally as it was dependent on signing by the politicians as tensions got higher in Europe the agreement forced both armies to provide help to each other.
in case of a war with Germany the French even promised a bold relief offensive within three weeks of a German attack the treaty was ratified by France on September 4th 1939 on the fourth day of German offensive on Poland however the French army didn’t attack Germany and provided only small help during the war in the form of the Saar offensive technically France had no obligation to come to Poland’s defence against the Soviet Union while Great Britain did in 1939 both nations had negotiated.
a defense pact with Poland though the agreement between Poland and France specifically named Germany as a potential aggressor whereas the British agreement referred to hostilities with a European power on the 25th of August two days after the molotov-ribbentrop pact the agreement of mutual assistance between the United Kingdom and Poland was signed the agreement contained promises of mutual military assistance between the nations.
if either was attacked by some European country due to the German expansionism Great Britain sought to discourage the German aggression to do this the British government wanted to show solidarity to Poland in a secret protocol of the pact the United Kingdom offered assistance in the case of an attack on Poland specifically by Germany but in the case of attacked by other countries the parties were required only to consult together on measures to be taken in common.
according to the Polish British agreement on the other hand Britain was legally obliged to attack the Soviet Union literally at once and provide all the support and assistance in its power per the 1939 act when the Soviet Union attacked the Polish ambassador in London requested help from Britain as soon as the Soviet Union attacked Lord Halifax said as regards Soviet aggression.
as we were free to take our own decision and to decide whether to declare war on the USSR or not the reason why the United Kingdom didn’t declare war on the Soviet Union is a scheming one thus between Poland and the UK was a secret protocol to the 1939 Anglo polish treaty that specifically limited the British obligation to protect Poland to aggression from Germany because the problem was very sensitive and it was questioned why Britain did nothing when the Red Army invaded eastern Poland.
the British government considered showing the secret part of the agreement however they decided not to Sir Alexander Cadogan of the Foreign Office explaining privately that to do so would only provoke curiosity about the existence of similar secret protocols attached to other treaties an answer given in the House of Commons in October 1939 revealed only that the poles had understood that the agreement should only cover the case of aggression by Germany.
the Soviet aggression was treated differently to German aggression however the British had already shown that they could not defend Poland against Germany and all they could do was to put pressure and to avoid war as much as possible in the 90 30s and when the situation got worse they declared war together with France but that was it the Soviet Union.
as well as Germany was a totalitarian state the Soviet Union was looking to expand westward claiming that some former territories of the previous Russian Empire were taken unfairly and they marched into Poland saying that some ethnicities needed their protection the British ambassador to Moscow Sir William seeds wrote in a secret telegram on the 18th of September 1939.
I do not myself see what advantage war with the Soviet Union would be to us and that a war aims are not incompatible with reasonable settlement on ethnographic and cultural lines neither the United Kingdom nor France were prepared for war of course both of them were strong powers but these countries were not looking for any conflict.
however Germany believed both France and Britain would not consider going further with their actions and they would back down even after declaring war this could have been a great chance for the Allies to end the war with Germany sooner by invading from the West considering that Germany had a small army for protection against a possible attack but nothing happened except for one small incursion into Germany territory by the French army indeed.
the Germans were right neither France nor Britain actually came to Poland’s aid they were not prepared for a conflict seeing the response the Allies had against Germany during the first days of the invasion of Poland it was certain that Britain and France weren’t going to follow up with another empty declaration of war against the Soviet Union even if pacts between Allies and Poland existed or not also speaking about regimes.
Germany and the USSR were rivals even in ideologies and the two countries were also historic rivals just more than 20 years passed since their last fight but somehow the two rival countries managed to create economic treaties and a surprising pact in the 1930s the attention was put on Germany and on their new expansionist ideas and less on the Soviet Union.
there was the fear that the Great War might happen again and the pact between Germany and the Soviet Union made the situation worse it was known that this was a non-aggression pact a neutrality pact not a proper military alliance by declaring war the Allies could have pushed the German and Soviet authorities to a military alliance or to a stronger bond that might last longer another reason to answer that question was the Polish geography.
Poland had the bad luck to be positioned on a huge plane with almost no natural defense between two undemocratic regimes that were seeking to expand and to quote and this ugly product of Versailles the Allies knew that and when the war broke out it was probably too late to do something to save Poland and the Polish people from a complete disaster.