Well,I don't know.At West Germany,at East Russia.There was no way in providing help to Poland.I guess that was the reasoning back then.Remember the so called "appeasement".Nobody wanted another war except those two lunatics (Hitler and Stalin) and the general idea was that appeasement would reunite peacefully Germany.Also Britain wanted to turn Germany eastward (I would do the same) against the communist Russia.Chamberlain failed eventually because he thought appeasement would eventually control Hitler and more important he did not realize that Britain is losing power and prestige.Nazism (and the Fascism brother) were basically unappeaseable.In fact Chamberlain actually recognize his mistakes.Britain could not effectively defend the new countries in the Eastern Europe (Poland,Czechoslovakia etc). Is for that they encouraged these countries to make concessions to Germany in a peaceful manner. But we all know the outcome.
As fro France,they were following very closely British foreign policy.It was a very weak state (40 governments under 20 different PMs) between 1917-1940.This decline deprived Britain from its most valuable ally against Germany.How else one would explain the fact that these two did nothing to stop rearmament race Hitler started?
So,I think the guarantee you speak about is regarding Poland itself.Romania was neutral,sort to speak. What guarantee could Britain offer Romania when they could not intervene for Poland.But I think it was not even the case.Romania was not priority at all for Britain then.Britain was concerned about Germany.And Germany had eyes on Poland...And,if I remember correctly ,Poland also got some Czech territory when Sudetenland was taken by Germany.
Later edit : BTW , was not Soviet Union the one who issued guarantees that Poland,Romania etc independence will be respected in the eve of Molotov-Ribentropp pact?
