March 5, 1940
The Katyn Massacre
The Katyn massacre was a mass execution of approximately 22,000 Polish prisoners of war, mainly officers and members of intelligentsia, carried out by the Soviet NKVD in spring 1940. The decision to conduct the executions was made on March 5, 1940, by order of the Political Bureau of the All-Union Communist Party (Bolsheviks), signed by Stalin. The executions were carried out in Katyn, Kharkiv, and Kalinin between April and May 1940.