Katyń Massacre Timeline: 1939 – present

1939

August 23

Molotov-Ribbentrop Pact is signed by Nazi Germany and the Soviet Union in a neutrality pact, delineating the spheres of interest between the two powers; it provides a written guarantee of non-belligerence by each party towards the other; and declares commitment that neither government will ally itself to or aid an enemy of the other party.

September 1

World War II begins; Germany invades Poland from the west.

September 17

The Soviet Union invades Poland from the east. Around 25,000 Polish military officers, senior NCOs, police officials, intellectuals and priests (ie Polish Elite) are arrested and interned on the territory which is now western Ukraine and western Belarus. They are either imprisoned locally or sent eastward to three special prisoner-of-war camps

September 19

Lavrentiy Beria orders the creation of the NKVD Administration for Affairs of Prisoners of War and Internees and for the Polish Elite POWs to be sent to camps administered by the NKVD in Kozelsk and Ostashkov in western Russia and Starobilsk in eastern Ukraine. There, they undergo lengthy interrogation and pressured to submit to Soviet loyalty.

1940

February 10

The first of four deportations removing between 1-2 million Poles from the Kresy (eastern Borderlands), Ukraine and Belarus to Kazakhstan and other remote Soviet locations.
10 February 1940
12-13 April 1940
28-29 June 1940
13-22 June 1941

March 5

The Soviet Politburo declares most Polish POWs and some of the elite in captivity “enemies of the Soviet Union” and orders death sentences for all of them, fearing that, if released, they will organise resistance movements against the Soviet occupation.

Spring

Over a period of weeks, more than 20,000 Poles are massacred by the Soviet NKVD killing squads. The murders are carried out at various sites and bodies are taken for mass burials to the Katyń forest in western Russia and other locations.

October 26

Beria orders the decoration of 125 NKVD staff involved in the Katyń operation. The entire operation was supervised by a troika of high-ranking NKVD officials: Vsevolod Merkulov, Bogdan Kobulov, and Leonid Bashtakov, who reviewed and authorised the execution lists. Merkulov and Kobulov were executed on 23 December 1953 along with Beria. Bashtakov was imprisoned in 1955.

1941

June 22

Germany attacks the Soviet Union via Soviet-occupied Poland. Its objectives were to destroy the Soviet military power, control oil reserves, industrial capacity and agricultural assets, advance Nazi ideology and eliminate the Soviet Union as a military threat. Stalin join the Allies against Hitler.

30 July

An agreement is signed between the Polish Government-in-Exile (located in London) and the Soviet Union. Present were Prime Minister Sikorski, Anthony Eden Foreign Minister, Prime Minister Churchill and Ivan Mayski Soviet Ambassador. The Soviet Government renounces territory gained under the Molotov-Ribbentrop Pact and grants “amnesty”  to Poles held prisoner in the Soviet Union.They are released for the formation of a Polish Army on Soviet territory.

August 6

General Władysław Anders is appointed Commander of the Polish Army on Soviet territory.

December 3

When General Anders requests that 15,000 Polish POWs whom the Soviets had once held at camps near Smoleńsk be transferred to his command, the Soviet government informs him that most of those prisoners have escaped to Manchuria and cannot be located.

1942

March

German occupiers learn of unmarked graves in Katyń, Mednoje (Mednoye), Piatichatki (Piatykhatky) and Bykownia (Bykivnia) but do not announce it until the following year.

1943

April 13

Nazi propaganda chief, Joseph Goebbels, announces the discovery of mass graves in their area of occupation containing a total of 4,443 corpses, of which over 1,700 are bodies of Polish officers who were shot in the back of the head. Goebbels hopes public knowledge of the Soviet crime will sow distrust between the Soviet Union and the Western Allies and weaken their alliance.

April 15

The Soviet authorities flatly reject the German accusations arguing that the Germans themselves committed the deed when they occupied the area in July 1941.
Churchill privately acknowledges to General Władysław Sikorski that the Soviet regime has probably committed the murders.

April 17

Polish Red Cross Technical Commission arrives in Katyń on the invitation of the Germans to supervise the humanitarian aspects of the exhumation and identification of the bodies. They continued until June gathering evidence of victims’ identities and recovering belongings.
The Polish Government-in-Exile in London, led by Władysław Raczkiewicz, Władysław Sikorski and Stanisław Mikołajczyk, requests the International Committee of the Red Cross to investigate the matter. The Soviet’s refusal of consent prevented ICRC’s participation.

April 24

Churchill, realising that bringing up the issue of Katyń at this stage would jeopardise the Alliance with the Soviet Union, informs Stalin that Great Britain will oppose any investigation of Katyń.

April 25

The Soviet Government breaks diplomatic relations with the Polish Government-in-Exile in London citing the appeal to the ICRC as one of the grounds. The Soviets then set about establishing a Polish Government composed of Polish communists.

April 28

Invited by the Germans, The International Medical Commission start their investigation to establish when and how the victims died.

April 30

The International Medical Commission completes its investigation concluding that the Soviet Union is responsible for the atrocity. The commission’s opinion is that the men were shot to death in the Spring of 1940.

May 1

As part of the Nazi propaganda effort, the Germans bring a group of American and British POWs to Katyń, including US Lt. Col. John H Van Vliet, to witness the exhumations. Vliet’s contemporary evidence recorded proof of Soviet responsibility for executions. It mysteriously vanished from official files, fuelling long-term investigations into whether the U.S. government suppressed evidence of Soviet guilt to protect its wartime alliance with Joseph Stalin.

May

Dr Jan Zygmunt Robel, a prominent Polish chemist and forensic toxicologist, begins work on the materials recovered from the Katyń pits. He played an invaluable, highly secretive role in preserving the historical truth of this crime.

June

The Polish Red Cross compiles its final documentation and reports after completion of the exhumations. The Polish Red Cross concentrated on who the victims were, the condition of the graves, clothing, personal effects, and documenting the exhumations. It deliberately refrained from formally assigning responsibility, consistent with its humanitarian mission

July 4

General Sikorski dies in a plane crash under suspicious circumstances.

August 7 – October 2

Since the Battle of Stalingrad, the Soviet army forced into a German retreat which led to a two month battle at Smoleńsk.

November

After the Red Army occupies Smoleńsk, the Soviet Union appoints an NKVD commission of inquiry of its own. It begins top secret work with the local NKVD falsifying evidence and removing all evidence of Soviet guilt, blaming the Germans for the Katyń murders.

1944

January 13

Nikolai Burdenko, Director of USSR Academy of medical Sciences, is appointed Chairman of the Special Commission to investigate the Katyń graves.

January 26

Official findings conclude that the Germans had murdered the Polish officers in the autumn of 1941. This became the official Soviet position until 1990.

Late April early May

Churchill asks Sir Owen O’Malley (British Ambassador to the Polish Government-in-Exile) to prepare an independent assessment of the evidence available to the British government.

May 31

In his report to Anthony Eden, O’Malley asserts Soviet guilt for the Katyń massacres. Churchill minutes, “All this is merely to ascertain the facts, because we should none of us ever speak a word about it.”

1945

May 8

World War II in Europe ends.
Upon being freed, Lt. Col. John H. Van Vliet gives his first report to US Army intelligence on what he witnessed at Katyń, a report that disappears until the release of US Archive files in 2012.

February

Robel’s Archive is removed from Kraków to the West but lost in a fire during transportation at Radebeul. Secret copies are hidden in Poland or spirited away to London and some material, including prisoners’ diaries surface after the war.

June

Dr Roman Martini, a Polish Prosecutor, begins his investigation into the Katyń massacre for the new Polish Communist authorities. He prosecuted individuals like Ferdynand Goetlow for allegedly spreading anti-Soviet propaganda regarding the massacre.

1946

30 March

Dr Martini is murdered. Jolanta Słapa and Stanisław Lubicz-Wróblewski, confessed to the crime for personal motives (revenge and robbery) replacing earlier conspiracy theories.

01-02 July

At the International War Crimes Tribunal at Nűremberg, the Soviet Prosecutors attempt to add responsibility for Katyń to the list of charges against the senior surviving Nazi leaders. However, the defence is able to call witnesses to refute the accusations of German responsibility. As a result, the Tribunal does not add Katyń to its list of charges, but neither does it make any judgement regarding ultimate responsibility.

1948

1948

The Katyn Murder in the Light of New Evidence (Zbrodnia katyńska w świetle dokumentów) is published. Józef Mackiewicz compiled documents regarding the massacre. primarily while serving with the Polish II Corps in Italy with an introduction by General Władysław Anders.
The book is credited as one of the earliest and most significant English-language exposures of Soviet responsibility for the 1940 execution of Polish officers.

1950

July 2

A United States Congressional Inquiry concludes and most Western historians now believe that the massacre was committed at the behest of the Soviet authorities.

1951

September 18

Subsequent to the inquiry, Congress sets up a committee to investigate the Katyń crimes after questions about the whereabouts of the missing Van Vliet report from 1945. Even ahead of the formal establishment of the committee, Van Vliet in 1950 makes a second written report on his impressions from Katyń.

1952

July 2

A United States Congressional Madden Committee finds the NKVD responsible and the Soviets are to blame for the massacre. It faults Roosevelt’s administration for suppressing public knowledge of the truth. The report suspects that pro-Soviet sympathisers within government agencies buried knowledge about Katyń.
However, the Soviet leaders continue to insist that the Polish officers were killed by the invading Germans in 1941.

1971

April

The KGB, successor to the NKVD, is put in charge of investigating burial sites in Bykownia. It is set to confirm the Soviet version that the burials are the result of Nazi killings in the Kyiv area in 1941-1943. The Soviets secretly burn revealed victims’ personal belongings and heavy bulldozers level the surface with a 2-meter layer of earth, in between crushing human remains and mixing them with the soil.

1976

September 18

The first monument in the world dedicated to the victims of the Katyń massacre is unveiled in Gunnersbury Cemetery in Acton, London. It is dedicated to the 14,500 Polish prisoners of war who disappeared in 1940. It is funded entirely by public donations from the UK Polish community, particularly the ex-combatant associations and the Anglo-Polish Society despite opposition from Soviet and British governments.

1987

December 24

Russian State Commission commences another investigation in Bykownia but its conclusion repeats the official Soviet narrative that these were victims of German crimes. It was to be the last investigation to place responsibility on the Germans.

1988

November

The newspaper Literaturnaya Ukraina publishes evidence that challenges the official version.

December 5

The Procuracy of the Ukrainian SSR open Criminal Case No. 50-0092 and the government reconstitutes the 1987 commission with a broader remit. 

1989

March 21

The commission formally acknowledges that the remains were those of victims of Stalinist political repression rather than Nazi atrocities. 

August 24

The Polish parliament elects Tadeusz Mazowiecki, a leading adviser to Solidarność (Solidarity), as Prime Minister. This marks the first non-Communist government in Poland since the Second World War and the first such government in the Soviet bloc.

September 13

Mazowiecki’s Solidarity-led Council of Ministers (government) is formally approved by parliament and took office.

October 9

Poland’s Prosecutor General, Józef Żyto, formally requests that the Soviet Prosecutor General open an investigation into the Katyn massacre. This is one of the first official actions by the new post-communist authorities directly treating the USSR as the responsible party.

1990

April 13

During President Wojciech Jaruzelski’s visit to Moscow, the Soviet government under Mikhail Gorbachev officially admits that the NKVD had carried out the massacre. The NKVD execution order listed 21,857 victims’ names. The locations of previously unknown mass graves were also disclosed at Mednoje and Piatichatki. The Polish government accepted this as confirmation of what it had already been asserting and seeking to prove.
This date is adopted for the annual commemoration in honour of those who perished in 1940.

1991

July 25 – August 7

A Polish team led by Stefan Śnieżka, then Deputy Attorney General of the Republic of Poland, starts exhumations at Piatichatki, a forested area located on the edge of Kharkiv, now Ukraine.

August
15 – 30

Stefan Śnieżka’s team turn their attention to Mednoje. Located approximately 180 kilometres north-west of Moscow, this area was never occupied by Nazis but remained under Soviet control at all times; the exhumations in Mednoje are of particular evidentiary value.

October 25

Excavations are carried out at Katyń as part of the investigation.
The Smoleńsk Soviet Regional Executive Committee declares 100 hectares at Katyń to be a protected zone; it mentions the presence of Soviet mass graves for the first time; it calls upon the procuracy and the KGB to conduct studies aimed at establishing sites and numbers of victims.

November 20-21

Russian Chief Military Prosecutor investigates the Katyń case. Some of the materials secretly archived by Jan Zygmunt Robel’s team in 1943-1945 are discovered in a building in Kharkiv.

1992

May 23

Polish President Lech Wałęsa visits Katyń saying “Katyn is a symbol of the truth about our relations. It is also a symbol of sincerity between our nations. The issue of these graves, and the truth about them, served as a pretext for the severing of relations between the Soviet and Polish governments in 1943. The lie about these graves was used to consolidate the imposed government, first in Lublin and then in Warsaw.”

October 14

The Russian government releases documents proving that the Soviet Politburo and the NKVD were responsible for the massacre and cover-up, and reveals that there may have been more than 20,000 victims.

October 27

A Russian-Polish bilateral agreement is signed to maintain and protect extra-territorial memorial sites. Katyń families visit Moscow at the invitation of Boris Yeltsin.

1993

August 25

Boris Yeltsin kneels before the Katyń cross in Warsaw and asks the Polish nation, “Forgive us if you can.”

1994

February 22

Government of the Russian Federation and the Government of the Republic of Poland sign a bilateral Agreement to establish the legal framework for the joint creation and maintenance of memorial sites.

5 May

Ukraine hands over to Poland the files of 3,435 Polish citizens arrested in the western regions of Soviet Ukraine—the so-called Ukrainian Katyn List (also known as Tsvetukhin List after Petro Tsvetukhin). This enabled Polish investigators to begin linking those victims with Bykownia. 

July 20

Alexander Lukashenko becomes President of Belarus.

September 5 – 15

A Polish research team led by the archaeologist Prof. Marian Głosek starts investigations in Katyń. The team includes archaeologists; forensic scientists: anthropologists, falerists, a historian, representatives of the Polish Red Cross, photographers and Father Zdzisław Peszkowski.

1995

1995

President Lech Wałęsa declares 1995 the “Year of Katyń” in Poland, marking the 55th anniversary of the massacre and promoting nationwide commemorations.

January 31

Smoleńsk Procuracy confirms the presence of mass Soviet burial sites at Katyń.

March 25

Russian-Polish protocol is signed agreeing construction of Polish military cemeteries within memorial complexes in Katyń and Mednoje.

June 4

On the 55th anniversary of the Massacre, the President of the Republic of Poland, Lech Wałęsa, lays the foundation stone – which had been consecrated by His Holiness Pope John Paul II – for the construction of the cemetery.

June 3 -September 22

A team under the leadership of Professor Andrzej Kola continues exhumations at Piatichatki.

June 6 -September 8

The Polish research team led by the archaeologist Prof. Marian Głosek returns to Katyń to continue their research. The team identifies the locations of five original mass graves of Polish prisoners of war from the Kozielsk camp.

1996

May 27 – September 14

Andrej Kola’s team completes exhumations.
In total, 75 mass graves are discovered of which 15 were identified as ‘Polish’ containing the remains of 3,820 corpses of POWS from the Starobelsk camp and 500 Polish civilians. The other 60 mass graves contain USSR citizens.

October 19

In accordance with the protocol signed with the Polish Government the previous February, Prime Minister Viktor Chernomyrdin signs Russian Government Resolution No. 1247, entitled:
“On the creation of memorial complexes at the burial sites of Soviet and Polish citizens – victims of totalitarian repression – at Katyń (Smolensk Oblast) and Mednoye (Tver Oblast).”
It establishes joint memorial complexes, implements the 1994 bilateral agreement and authorises the building of complexes at Katyń and Mednoje.

1998

1998

Additional explorations at Katyń take place. The construction of Katyń Memorial Complex commences.

2000

July 28

Official opening and dedication of the completed Polish War Cemetery at Katyń followed by Mednoje the next day and Piatichatki the day after.

2003

January

Włodzimierz Odojewski publishes his novel “Silent Undefeated”, a Katyń story originally commissioned by Andrzej Wajda with the view to a future film project.

2004

September 21

The Russian Chief Military Procuracy investigation of Katyń is closed without identifying or prosecuting those responsible. The Russian authorities concluded that the killings did not constitute genocide and classified much of the case file, making it unavailable to Polish prosecutors.  

November 30

Following the outcome of the Russian investigation, the Polish Institute of National Remembrance launches its own Katyń investigation.

2007

September 17

Wajda’s film “Katyń” premieres in Poland and then across the world throughout 2008 and 2009 including Russia on 18 March 2008.

November 14

The Polish Sejm declares the commemoration held each year on April 13 as “The Worldwide Day of Memory of Victims of the Katyń Crime”. The date marks the anniversary of the German announcement in 1943 and the Russian admission of guilt in 1990.

November 19

Relatives of 12 Katyń victims lodge an application to the European court of Human Rights on the grounds that the Russian military prosecutor’s investigation was ineffective, was terminated without identifying or prosecuting those responsible, failed to rehabilitate victims under Russian law as victims of political repression, denied access to official information and families were treated in an inhumane and degrading manner during the process.

2009

July

The consecration of memorial stone in the Katyń Valley of Death in marking mass graves of Soviet terror victims takes place.

2010

April 7

The Russian Prime Minister, Vladimir Putin, joins Polish Prime Minister, Donald Tusk, at a ceremony commemorating the massacre at Katyń, marking the first time that a Russian leader has taken part in such a commemoration.

April 10

A plane carrying Polish President, Lech Kaczyński to commemorate the 70th anniversary of the massacres crashes near Smoleńsk killing all 96 members of the delegation. Victims include his wife, the head of the national security bureau, the president of the national bank, the army chief of staff, and a number of other Polish government officials.

August 10

Russian President, Dmitry Medvedev, awards film director Andrzej Wajda the Order of Friendship for his “great contribution to the development of Russian-Polish relations in the field of culture,” recognising in particular his role in fostering dialogue through his film Katyń. 

November 26

The Russian State Duma adopts its landmark declaration On the Katyn Tragedy and its Victims, acknowledging that the massacre had been carried out on Stalin’s direct orders and calling for continued archival research, verification of the lists of victims, restoration of victims’ good names, and clarification of the remaining circumstances of the crime. 

2011

October 21

Russian Foreign Minister Sergey Lavrov states that Russia was prepared to consider a formal request for the legal rehabilitation of the victims of the Katyń massacre, provided it could be resolved within the framework of Russian law. Although the announcement raised hopes of a change in policy, no general rehabilitation of the victims subsequently takes place.  

2012

September 10

The US National Archives releases about 1,000 pages of newly-declassified records related to the Katyń massacre. Among them are the newly-declassified US army documents proving that two American POWs, Stewart and Van Vliet,  wrote encoded messages to Army intelligence, MIS-X, soon after their 1943 visit to Katyń, pointing to Soviet guilt.

September 21

The Polish War Cemetery at Bykownia is officially opened by the Presidents of Poland and Ukraine, recognising the site as the burial place of Polish victims of the 1940 NKVD executions. 

2013

October 21

The European Court of Human Rights rules that Russia failed to comply with its obligations to adequately investigate the massacre of more than 20,000 Polish Prisoners-of-War by the Soviet Secret Police in 1940. But the court says it has no jurisdiction over the massacre itself or the subsequent treatment of the relatives of the dead.
The case remains historically significant because it:
– brought the inadequacies of the Russian investigation before an international court;
– established that Russia failed in its duty to cooperate with the European Court by withholding crucial documents;
– produced the most detailed judicial review to date of the Russian investigation into the Katyń massacre.

2018

April 20

The reconstructed Russian section of the Katyń Memorial Complex is officially reopened. A new museum and exhibition centre, Memorial Wall and the monument Shooting are unveiled. The reconstruction does not alter the adjacent Polish War Cemetery, but the accompanying historical exhibition later attracts criticism in Poland for its interpretation of Polish–Russian relations.

2021

The Katyń Memorial Complex is reorganised as a branch of the State Central Museum of Contemporary History of Russia, following which the memorial’s historical interpretation increasingly reflected official Russian state narratives.

2022 onwards

Following Russia’s invasion of Ukraine in 2022, joint Polish–Russian commemorations end and instead are held separately. Disputes over the memorial sites intensify and Polish national symbols and flags removed and the Russian section expanded. The removal is condemned by the Federation of Katyn Families and The Office for War Veterans and Victims of Oppression (UdsKiOR) authorities as a breach of the 1994 agreement between the governments of Poland and Russia concerning these graves and memorial sites.

2026

April

Russian authorities open an exhibition entitled “Ten Centuries of Polish Russophobia” at the Katyn memorial complex, close to the mass graves. The exhibition has been condemned as historical revisionism and as a return to the Soviet-era narrative concerning Katyn supported American academic Grover Furr.

The Hoover archives provide an alternative perspective.