Katyn massacre

1940MajorContested

The Soviet secret police shoot about 22,000 Polish officers, police and professionals at Katyn and other sites. Moscow blames Germany for 50 years before admitting guilt in 1990.

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Contested history

Consensus: The NKVD executed the prisoners on Stalin's orders in spring 1940; the USSR admitted this in 1990 and released the execution order in 1992.

Soviet NKVD killed them in 1940Established

Soviet archives released in 1990 and 1992 include the Politburo order, confirming earlier German and US congressional findings.

Germany committed the massacre in 1941Debunked

This was the Soviet version pressed at Nuremberg; the tribunal did not uphold it and Moscow admitted guilt in 1990.