The relationship between the Soviet Union and Poland was tenuous at best during World War II for a variety of reasons , and became more so , after the 1940 Katyn massacre of over 20,000 Polish servicemen by the Soviets came to light . However , pragmatic general Władysław Sikorski was still open to some form of normalisation of Polish-Soviet relations , while general Władysław Anders was vehemently opposed . To boost morale , Sikorski began a tour of inspection of the Polish forces stationed in the Middle East in May 1943 , tending to political affairs where necessary
Katyn massacre
Katyn massacre
1943 Gibraltar B-24 crash