In 1943, a mass grave of Polish officers was discovered in the Katyn Forest near Smolensk in Russia. The radio announcement was made by a German radio station; the alleged massacre was apparently carried out by the Soviet secret police, the NKVD. Soviet History notes that “the claim was denounced by Stalin as a ‘monstrous invention by the German-fascist scoundrels’ designed to sow discord among the war-time allies.” The Soviets continually denied having any involvement in the massacre, blaming the German forces who also invaded Poland at the time. Upset at the number of bodies, the Polish government begged the Red Cross to begin an investigation of the massacre, not fully believing that the Germans had any involvement. Thus began the lengthy trials at Nuremberg to discover what really happened at Katyn.

The beginning of this story starts with the invasion of Poland by both Nazi and Soviet forces in 1939; this set both Germany and Russia as suspects in the massacre. The Russians legitimized their invasion by claiming “it was liberating Ukrainian and Belorussian toilers from their oppressive Polish rulers.” Once the Soviets had access to the Poles, they were “placed in “special” (concentration) camps, where, from October to February, they were subjected to lengthy interrogations and constant political agitation.” The CIA article notes that Stalin was simultaneously dealing with logistics to transport the Poles and the “disastrous 105-day war against Finland. The Finns inflicted 200,000 casualties on the Red Army and destroyed tons of material–and much of Russia’s military reputation.” Anxious to move forward, Stalin signed the warrant for the deaths of more than 20,000 people on March 5, 1940.

“To Comrade Stalin
A large number of former officers of the Polish Army, employees of the Polish Police and intelligence services, members of Polish nationalist, counter-revolutionary parties, members of exposed counter-revolutionary resistance groups, escapees and others, all of them sworn enemies of Soviet authority full of hatred for the Soviet system, are currently being held in prisoner-of-war camps of the USSR NKVD and in prisons in the western provinces of Ukraine and Belarus. […] In view of the fact that all are hardened and uncompromising enemies of Soviet authority, the USSR NKVD considers it necessary: […]together with the cases of 11,000 members of various counter-revolutionary organizations of spies and saboteurs, former land owners, factory owners, former Polish officers, government officials, and escapees who have been arrested and are being held in the western provinces of the Ukraine and Belarus and apply to them the supreme penalty: shooting.”
The above text is taken directly from the order that was signed by Stalin; this order was carried out from April to May 1940. Katyn was the site with the largest number of bodies, which were discovered by German forces in 1943. Despite overwhelming evidence that Russia was responsible, they continued to deny their involvement until 1990 when Gorbachev presented documents that undoubtedly linked Stalin to these massacres. However, the CIA article also notes that Gorbachev did not give full disclosure in the interest of preserving Communist Party’s less-than-stellar reputation. These actions really show how far Stalin was willing to take punishment of people who were innocent. He truly into some hot water in the years before WWII and it backfired horribly, turning into one of the most infamous massacres of World War II, leaving a guilt on the Russian state that still lingers to this day.
Sources
http://www.soviethistory.org/index.php?page=subject&SubjectID=1943katyn&Year=1943&navi=byYear
http://www.soviethistory.org/index.php?page=article&ArticleID=1943katyn4&SubjectID=1943katyn&Year=1943
https://www.cia.gov/library/center-for-the-study-of-intelligence/csi-publications/csi-studies/studies/winter99-00/art6.html
Image #1: http://www.calvin.edu/academic/cas/gpa/posters2.htm
Image #2: “Zbrodnia katyńska w świetle dokumentów / z przedm. Władysława Andersa” from Wikipedia article, “Katyn Massacre”