This article presents the historiography of the massacres of Poles in Volhynia and Eastern Galicia, as presented by historians in Poland and Ukraine after World War II.
Beginning in March 1943, and lasting until early 1945, a violent ethnic cleansing operation against Poles – conducted primarily by the Ukrainian Insurgent Army (UPA) – occurred in the regions of Eastern Galicia and Volhynia (now in Western Ukraine). According to political scientist Nathaniel Copsey, research into this event was quite partisan until 2009 (with some exceptions), and dominated by Polish researchers, some of whom lived there at the time or are descended from those who did. The most thorough is the work of Ewa and Władysław Siemaszko, the result of years of research conducted with the goal of demonstrating that the Poles were victims of genocide. Nonetheless, the 45 years of state censorship resulted in an excessive supply of works described as "heavy in narrative", "light in analysis" and "inherently – though perhaps unconsciously – biased against Ukrainians."
Polish historiography.
Communist Poland.
The Polish historiography of the Volyn tragedy during the dictatorship of the communist party can be broken down into three periods: 
In the early People's Republic of Poland, the question of the Polish–Ukrainian conflict was never a subject of independent studies. Ukrainian historian Roman Hrytskiv believes that Polish Communists avoided this subject as it could raise questions regarding the Polish population in Western Ukraine. 
Paweł Machcewicz from the Polish Institute of National Remembrance suggests two reasons why, up until the collapse of communism, censorship blocked the subject of the massacres of Poles in Volhynia and Eastern Galicia perpetrated by the OUN-UPA: 
As the subject matter of the anti-Polish action in Volhynia and Eastern Galica was prohibited, in Polish popular remembrance of the Ukrainian Insurgent Army (UPA), the site of the mass killings was transferred to Bieszczady and Eastern Lubelszczyzna; and thus communists were able to portray Operation Vistula as the only effective way of liquidating the UPA network. The theme of UPA "terrorism" was occasionally brought up in order to affirm the actions of the "people's government". According to Hrytskiv, Polish studies branded all Ukrainian nationalist organizations as anti-Polish, criminal and collaborationist.
New studies were initiated in the early 1970s based on factual information. Under the influence of the Soviet historiography, Polish historians continued to expound the mistaken Soviet concept of Ukrainian bourgeoise nationalists, viewed in their own specific manner. This category includes the works of Ryszard Torzecki, who explained the reason for the conflict as Hitlerite politics based on the tenet of divide and conquer, the chauvinism of Ukrainian nationalists, and Ukrainian-Polish disagreements in the interbellum, which were used by the Nazis in their interests. Similar concepts were formulated by A. Szczesiak and W. Szota in a publication that was soon removed from sale and libraries. Officially the book was dedicated to the activities of the Ukrainian nationalists in the interbellum but it also explained that the conflict had its origins in the late 19th century, and that the Volyn tragedy was a continuation of the terror campaigns of 1918-1939. This work investigated in detail the Ukrainian-Polish negotiations from 1942-45 to stop the conflict and to unite to fight a common foe – the USSR. This study brought about a re-evaluation of the UPA within the USSR itself.
The next significant study was published in the mid-1980s by Edward Prus – "Heroes under the sign of the Trident" (1985), which employed a journalistic and propagandistic style. Prus was the first to introduce the terms and concepts such as the Ukrainian "slaughter" of Poles. He compares the anti-Polish actions in Volyn and Galicia without the use of academic citations. According to Hryckiw, Prus's work has no scientific merit. In his opinion, the use of a journalistic style, falsification, and manipulation reflect the state of Polish historiography in the last years of the communist Poland.
Independent Poland.
1989 marked the end of the Polish totalitarian state and a new era in Polish historiography. In the light of Polish independence the subject of Ukrainian–Polish relations became a growing concern. The first study to be published was Tadeusz Olszański's 1989 article which shattered previous understandings of the OUN. He ascribes the reason for the Volyn tragedy to the inadequate policies of the Polish government in the interbellum and the destruction of moral society during the Soviet and German occupations. Olszański notes that in pre-war Poland, a Ukrainian nationalist movement could develop relatively freely even in the most radical forms, including the use of terror, and that the Polish state wasn't able to solve the problems concerning coexistence of Poles and Ukrainians, which resulted in popularization of nationalist and communist movements among the Ukrainians.
Olszański introduces the term "de-polonisation". Olszański suggests that the OUN expected a return to the situation as it was from 1918, when Poles and Ukrainians fought over disputed territories, and that the Ukrainian leadership wanted an absence of Polish population and Polish military activity. "De-polonization" action started in March 1943. Contrary to what Ukrainian emigré authors claim, the fact of Ukrainian initiative and the unprovoked character of the action is confirmed by the German documents. In the article from 1991, he divides "Volhynian terror" into the following stages:
Olszański underlines the influence of numerous provocations by the NKVD and Soviet partisans in the occupied zones in directing conflict against the UPA. Retaliatory actions by Polish forces and the negative view of the Polish underground to Ukrainian independence were also factors. In the second period Olszański states that the Polish underground and the communists initiated a number of anti-Ukrainian terrorist actions. Ukrainian responses were restrained as at this time negotiations were being undertaken for a united Ukrainian–Polish front against Moscow. This was the first step to an understanding with the Poles, which in 1945 was affirmed by the tactical understanding between the UIA and AK. In the words of Olszawski, this was the end of conflict between these national movements, who would now wage a joint battle against the communist regime in Poland.
The UPA was unable to conduct the action alone. It mobilized Ukrainian peasants on a large scale, who were later given Polish properties. Vast numbers of peasants participating in anti-Polish attacks, together with UPA units or individually, were also motivated by numerous Banderist agitators and by communist agents from the north of Volhynia. Olszański sees the role of Soviets in the events as insufficiently explained. He points that field organizations of the OUN were penetrated by communist agents and in some instances Soviet units disguised as UPA murdered Poles to gain support of local Polish population.
According to Olszański, the responsibility for the terror lies mostly on the OUN-B leadership, which decided to perform the large-scale anti-Polish action.
Olszański expressed view that the goal of the action was to expel Poles and not to exterminate them. Ten years later, in the post script to his previous article, he admitted that he was wrong: "More and more documents prove not only that the de-polonization action was a planned military operation and that the order from OUN-UPA leadership existed (though still not found), but also that the purpose of this operation was physical extermination (murder) of at least most of the Polish population of these lands, and not only – as I erroneously believed – expulsion. Thus it was the crime of genocide."
Zbigniew Kowalewski's study (1993) stated that the role of the auxiliary police and its collaboration with Soviet Polish diversionist-partisan groups provoked the Ukrainians to use force. These actions were not just those of the OUN and UPA, but also Soviet partisans, auxiliary police and other independent groups. Kowalewski introduces the thesis that the reason why OUN changed its strategy regarding the Poles in 1944–45 was in order to form a unified Polish-Ukrainian front against the USSR. This would explain the waves of OUN propaganda that were spread in the Polish population regarding the formation of a unified front and the cessation of retributive actions. The Ukrainian and some sections of the Polish population understood that without an independent Poland there could not be an independent Ukraine.
The destruction of the totalitarian system in Poland allowed another direction in Polish historical studies fuelled by the previous studies published under the Communist regime. One of the first such studies was undertaken by J. Turowski and Władysław Siemaszko in 1990, based on 350 eyewitness accounts from veterans of the Polish Home army regarding the anti-Polish terror in Volyn. Subsequently, Władysław with daughter Ewa Siemaszko – in their own ten-year-long research project – went on to document murders committed on Polish citizens by Ukrainian Insurgents in some 1,865 villages and towns of Volhynia during the Nazi and Soviet occupations. Their books were based on witness accounts, court documents including transcripts from trials of Ukrainian war criminals, as well as the Polish national archives and statistical censuses. In 2010 the Institute of National Remembrance (Bulletin No. 7–8, 116–117) published an overview by Ewa Siemaszko of their joint research with the following up-to-date table of collected data.
The fall of the Communist system in Poland gave fuel to two directions in Polish historiography regarding the Ukrainian–Polish conflicts: liberal-democrаtic and nationalistic. The first group has focused on the reasons for the inter-ethnic conflict in Western Ukraine. This group is subscribed to by most professional historians. The second group focuses on the problems of anti-Polish terror by the UPA. This movement is supported by former inhabitants of Volyn and Galicia and members of the various Kresy societies.
The Polish emigre centre in London at this time began to actively support a nationalist view on the Volyn tragedy. In 1992, a magazine called "Na rubieży" began publishing studies by W. Siemaszko, E. Prus and Wiktor Poliszczuk. Attempts were made to document the Polish victims of Ukrainian nationalists, with the inclusion of unverified or even falsified information. Numerous memoirs were published, dominated by the works of E. Prus. Many of these publications were printed by the newly established Nortom publishing house in Wrocław.
The liberal-democratic movement is represented by the works of Ryszard Torzecki which reviewed the thesis put forward during the communist administration and developed a framework for further scholarship. Torzecki argues that the territorial integrity of Volyn lay in the Polish population. From this point of view the author examines anti-Polish actions, the spontaneous actions of the peasants, and the influence of OUN propaganda on their fight for social justice. Describing concrete incidence of terror in Volyn, he states that the pivotal moment for the development of bloodshed came with the transfer of armed Ukrainian police into the forests. This act raised the number of OUN-B dependent groups with people who had experience in the ethnic cleansing of Jews. Secondly it initiated a mass movement of Poles into the ranks of the auxiliary police, which further escalated the situation. The author postulates that anti-Polish terror may have been planned, it had as its main purpose to chase out the Poles. Torzecki states that the raid by Sydir Kovpak introduced a significant destabilizing factor to the region and initiated the formation of Ukrainian National Defence – the group which first initiated the anti-Polish actions. The discussions between the Polish and Ukrainian sides were doomed to failure because they were based on tactical considerations.
Although Torzecki states that in 1943–44 the attempts to curtail the conflict between Ukrainian and Polish nationalism were doomed to failure, in his opinion it was OUN-UPA that could have stopped the conflict and did not. He lays blame personally on Roman Shukhevych, who was accustomed to dealing with problems from a position of force, and would consider using terror on the civilian population.
In his 1997 study, Filar came to the conclusion that the sole result of the actions of OUN and UPA were to destroy the Polish population. This he bases on a command given by Klym Savur regarding the liquidation of the urban Polish population. Information about this command was obtained from a criminal deposition of Yuri Stelmashchuk which existed in the archive of the SBU in Volyn. The command was a secret one given orally by D. Kliachkivsky to liquidate all Polish elements in the region. Filar comes to the conclusion that UPA consciously aimed their actions against the civilian Polish population. He also concludes that the UPA made its priority the extermination of Polish elements rather than fighting the occupiers.
Grzegorz Motyka and Rafal Wnuk point out