The term refers to several events , including the treatment of Czechoslovakia during the Munich Agreement and the resulting occupation by Germany , as well as the failure of France and the UK to aid Poland when the country was invaded by Germany and the Soviet Union in 1939 . The same concept also refers to the concessions made by the United States and the United Kingdom to the Soviet Union during the Tehran , Yalta , and Potsdam conferences , to their passive stance during the Warsaw Uprising against Nazi occupation , and post-war events , which allocated the region to the Soviet sphere of influence and created the communist Eastern Bloc
Yalta
Yalta Conference
Western betrayal