The start of World War II is marked by Germany's invasion of Poland on September 1, 1939, which led Britain and France to declare war on Germany. Often overlooked is the Soviet Union's role; they invaded Poland from the east on September 17, 1939, as part of a secret clause in a non-aggression pact with Germany. Despite Poland's strong army, they were overwhelmed by Germany's modern military and the Soviet invasion. The Soviets captured Polish troops and civilians, leading to mass deportations and executions, including the Katyn massacre where approximately 22,000 Poles were killed by the NKVD. The truth about Katyn was suppressed during the war to maintain the Allied alliance against Hitler, and it wasn't until after the fall of the Soviet Union that Russia admitted Stalin's responsibility for the massacre.
Here are the key facts extracted from the text:
1. Germany invaded Poland on September 1, 1939.
2. Britain and France declared war on Germany on September 3, 1939, following an agreement they had with Poland.
3. The Soviet Union, led by Stalin, had a non-aggression pact with Germany, which included a secret clause to invade Poland from the east.
4. The Soviet Union invaded Poland on September 17, 1939.
5. Poland had a large and well-trained army, but it had weaknesses, including an over-reliance on horse cavalry and outdated artillery and air force.
6. The Polish military had 1.75 million regular troops and 500,000 in reserve in 1939.
7. The Soviet Union captured 400,000 Polish troops, and 42,000 of Ukrainian or Belarusian ethnicity were released.
8. 125,000 Polish prisoners were sent to camps run by Stalin's secret police, the NKVD.
9. The NKVD began repression against Polish citizens, including intellectuals, military officers, and clergy.
10. In March 1940, Stalin signed an order to execute 25,700 Polish nationalists and counter-revolutionaries.
11. The killings began after April 3, 1940, and 21,857 Polish prisoners were shot at various locations.
12. The Katyn massacre occurred in the Katyn forest, where 12,000 Polish prisoners were shot and buried in mass graves.
13. The Soviet Union denied any involvement in the massacre, and instead blamed the Germans.
14. In 1943, the Germans investigated the massacre and formed the Katyn Commission with international forensic surgeons.
15. The commission's findings were suppressed by the Allies, who needed the Soviet Union's help in the war against Hitler.
16. In 1989, Soviet academics finally admitted that Stalin had ordered the Katyn massacre.
17. In 1990, Soviet Premier Mikhail Gorbachev named the NKVD as the responsible organization for the massacres.
18. In 1990, President Boris Yeltsin ordered the transfer of documents related to Katyn from Russia to Poland.
19. In 2010, the Russian parliament officially admitted that Stalin and Beria were responsible for the massacres.
20. No one has ever stood trial for the Katyn massacre, and many documents related to the event remain classified.