In 1942 Jan Karski reported to the Polish, British and U.S. governments on the situation in Poland, especially the Liquidation of the Warsaw Ghetto and the general systematic extermination of the Jews nationally. However, he did not know of the existence of gas chambers, instead repeating the belief (common at the time) that Jews were being killed with electricity. He met with Polish politicians in exile, including the Prime Minister, Władysław Sikorski, as well as with members of political parties such as the Socialist Party, National Party, Labor Party, People's Party, Jewish Bund and Poalei Zion. He also spoke to Anthony Eden, the British Foreign Secretary, and included a detailed statement on what he had seen in Warsaw and in Bełżec. In 1943 in London he met the author and journalist Arthur Koestler. He then traveled to the United States and reported to President Franklin D. Roosevelt. FDR reacted to Karski's report by inquiring jokingly into animal rights abuses (specifically, horses). His report was a major factor in informing the West.
Karski met also with many other government and civic leaders in the United States, including Felix Frankfurter, Cordell Hull, William Joseph Donovan, and Stephen Wise. Karski presented his report to media, to bishops of various denominations (including Cardinal Samuel Stritch), to members of the Hollywood film industry and artists, but without success. Many of those he spoke to did not believe him, or judged his testimony much exaggerated or saw it as propaganda from the Polish government in exile.
In 1942 members of Polish government in exile published an official Polish protest against systematic murders of Jewish population in occupied Poland, based on the Jan Karski report and titled "The Mass Extermination of Jews in German Occupied Poland". The Poles addressed their protest to the 26 Allies who had signed the Declaration by United Nations on 1 January 1942. In response, the Allied Powers issued on December 17, 1942 an official statement titled Joint Declaration by Members of the United Nations Against Extermination of the Jews. The statement was read to the British House of Commons in a floor speech by Foreign secretary Anthony Eden, and published on the front page of the New York Times and by many other newspapers.
In 1942 Szmul Zygielbojm Jewish-Polish socialist politician, leader of the General Jewish Labor Bund in Poland, and a member of the National Council of the Polish government in exile wrote in English a booklet titled Stop Them Now. German Mass Murder of Jews in Poland, with a foreword by Lord Wedgwood.
From April 19, 1943 through April 30, 1943, during the Warsaw Ghetto Uprising of 19 April to 16 May, representatives of the governments of the United Kingdom and the United States held an international conference at Hamilton, Bermuda. They discussed the question of Jewish refugees who had been liberated by Allied forces and of those who still remained in Nazi-occupied Europe. The only agreement made was that the war against the Nazis must be won. The US did not raise its immigration quotas and the British prohibition on Jewish refugees seeking refuge in the British Mandate of Palestine remained in place. A week later, the American Zionist Committee for a Jewish Army ran an advertisement in the New York Times condemning the United States efforts at Bermuda as a mockery of past promises to the Jewish people and of Jewish suffering under German Nazi occupation. Szmul Zygielbojm, a member of the Jewish advisory body to the Polish government-in-exile, committed suicide in protest.
From April 1942 to February 1943, British Intelligence intercepted and decoded radio messages sent by the “German Order Police”, which included daily prisoner returns and death tolls for ten concentration camps, including Auschwitz.
The United States Office of Strategic Services (the predecessor of the Central Intelligence Agency (CIA) and which had been established in 1941-1942 to coordinate intelligence and espionage activities in enemy territory) received reports about Auschwitz during 1942.
At the beginning of Operation Reinhard, the principal source of intelligence for the Western Allies about the existence of Auschwitz was the Witold's Report, forwarded via the Polish resistance to the British government in London. It was written by the Polish Army Captain Witold Pilecki who spent a total of 945 days at the camp – the only known person to volunteer to be imprisoned at Auschwitz. He forwarded his report about the camp to Polish resistance headquarters in Warsaw through the underground network known as Związek Organizacji Wojskowej which he organized inside Auschwitz. Pilecki hoped that either the Allies would drop weapons for the Armia Krajowa (AK) to organize an assault on the camp from the outside, or bring in the Polish 1st Independent Parachute Brigade troops to liberate it. A spectacular escape took place on 20 June 1942, when Kazimierz Piechowski (prisoner no. 918) organized a daring passing through the camp's gate along with three friends and co-conspirators, Stanisław Gustaw Jaster, Józef Lempart and Eugeniusz Bendera. The escapees were dressed in stolen uniforms as members of the SS-Totenkopfverbände, fully armed and in an SS staff car. They drove out the main gate in a stolen Steyr 220 with a smuggled first report from Witold Pilecki to Polish resistance. The Germans never recaptured any of them. By 1943 however, Pilecki realized that no rescue plans existed in the West. He escaped from the camp on the night of April 26–27, 1943.
The first written accounts of Auschwitz concentration camp was published in 1940/41 in the Polish underground newspapers "Polska żyje" ("Poland lives") and "Biuletyn Informacyjny" From 1942 members of Bureau of Information and Propaganda of the Warsaw Area Home Army also began to publish short booklets based on the experiences of escapers. The first was the fictional "Auschwitz. Memories of a prisoner" written by Halina Krahelska and published in April 1942 in Warsaw The second publication was also produced in 1942 by the PPS WRN book "Obóz śmierci" (eng. "Camp of death") written by Natalia Zarembina. In the summer of 1942 a book about Auschwitz titled "W piekle" (eng. "In Hell") was also written by the Polish writer, social activist and founder of Żegota - Zofia Kossak-Szczucka
Polish reports about Auschwitz was also published in English version. Booklet of Zarembina was translated on English and published by Polish Labor Group in New York in March 1944 with title "Oswiecim, Camp of Death (Underground Report)" with foreword of Florence Jaffray Harriman. In this report from 1942 gasing of prisoners was described.
Auschwitz site Plans, originating from the Polish Government, were passed on to the British Foreign Office on 18 August 1944. Władysław Bartoszewski, himself a former Auschwitz inmate (camp number 4427), said in a speech: "The Polish resistance movement kept informing and alerting the free world to the situation. In the last quarter of 1942, thanks to the Polish emissary Jan Karski and his mission, and also by other means, the Governments of the United Kingdom and of the United States were well informed about what was going on in Auschwitz-Birkenau."
On April 7, 1944, two young Jewish inmates, Rudolf Vrba and Alfréd Wetzler, had escaped from the Auschwitz camp with detailed information about the camp's geography, the gas chambers, and the numbers being killed. The information, later called the Vrba-Wetzler report, is believed to have reached the Jewish community in Budapest by April 27. Roswell McClelland, the U.S. War Refugee Board representative in Switzerland, is known to have received a copy by mid-June, and sent it to the board's executive director on June 16, according to Raul Hilberg. Information based on the report was broadcast on June 15 by the BBC and on June 20 by The New York Times. The full report was first published on November 25, 1944, by the U.S. War Refugee Board, the same day that the last 13 prisoners, all women, were killed in Auschwitz (the women were "unmittelbar getötet"—killed immediately—leaving open whether they were gassed or otherwise killed).
Auschwitz was first overflown by an Allied reconnaissance aircraft on April 4, 1944, in a mission to photograph the synthetic oil plant at Monowitz forced labor camp (Auschwitz III).
On 26 June, 71 B-17 heavy bombers on another bomb run, had flown above or close to three railway lines to Auschwitz.
On July 7, shortly after the U.S. War Department refused requests from Jewish leaders to bomb the railway lines leading to the camps, a force of 452 Fifteenth Air Force bombers flew along and across the five deportation railway lines on their way to bomb Blechhammer oil refineries nearby.
Buna-Werke, the I.G. Farben industrial complex located adjacent to the Monowitz forced labor camp (Auschwitz III) located 5 kilometres (3.1 mi) from the Auschwitz I camp was bombed four times, starting at 20 August 1944 until 26 December 1944. On December 26, 1944, the U.S. 455th Bomb Group bombed Monowitz and targets near Birkenau (Auschwitz II); an SS military hospital was hit and five SS personnel were killed.
The Auschwitz complex was photographed accidentally several times during missions aimed at nearby military targets. However, the photo-analysts knew nothing of Auschwitz, and the political and military hierarchy didn't know that photos of Auschwitz existed. For this reason, the photos played no part in the decision whether or not to bomb Auschwitz. Photo-interpretation expert Dino Brugioni believes that analysts could have easily identified the important buildings in the complex if they had been asked to look.
Since the controversy began in the 1970s, a number of military experts have looked at the problems involved in bombing Auschwitz and the rail lines and have concluded that it would have been extremely difficult and risky and that the chances of achieving significant results would have been small. It appears reasonable to assume that John J. McCloy was accurate in his early statements that the idea was never discussed with President Roosevelt. Later in life John J. McCloy may have found it expedient to share with FDR the blame heaped on him by average people and by those who seek to blame somebody in addition to the Germans for the Holocaust.
A 2004 documentary, Auschwitz; the forgotten evidence included interviews with historians William Rubinstein and Richard Overy. It mentioned the Jewish Agency's request to the Allies on 6 July to bomb Auschwitz and showed the aerial reconnaissance photographs. It then examined the operational and technical feasibility aspects, in two categories: precision bombing by Mosquito-type aircraft, and area bombing by larger aircraft. It considered that precision bombing of railway lines was so common by 1944 that the Germans had specialist teams that could repair damage within hours or days. The inmates' food supplies were assumed to come by rail, and so an unrepaired railway would cause them hardship. Area bombing risked killing too many prisoners.
From March 1944 onwards, the Allies were in control of the skies over Europe. According to historian David Wyman the 15th U.S. Army Air Force, which was based in Italy, had the range and capability to strike Auschwitz from early May 1944. General Ira C. Eaker, the American Mediterranean Allied Air Forces Commander, whose airplanes were already bombing nearby Auschwitz, in July 1944 visited the Air Ministry in London. When the request to bomb Auschwitz was put to Churchill, he gave it his full support. He regarded it as something that the American daylight bombers could and should do.
On August 24, 1944, the U.S. Army Air Forces carried out a bombing operation against a factory adjacent to the Buchenwald concentration camp. Despite perfect weather conditions, 315 prisoners were killed, 525 seriously harmed, and 900 lightly wounded.
"No proposals to bomb either Auschwitz or the rail lines were made by anyone until May or June 1944" – wrote historian William Rubinstein, former President of the Jewish Historical Society of England. The first such proposal was made by a Slovak rabbi, Michael Dov Ber Weissmandel, to the Jewish Agency on May 16, 1944. At about the same time, two officials of the Jewish Agency in Palestine separately made similar suggestions. Yitzhak Gruenbaum made his to the U.S. Consul-General in Jerusalem, Lowell C. Pinkerton, and Moshe Shertok made his to George Hall, the British under secretary of state for foreign affairs. However, the idea was promptly squashed by the Executive Board of the Jewish Agency. Rubinstein says that on 11 June 1944, the Executive of the Jewish Agency considered the proposal, with David Ben Gurion in the chair, and it specifically opposed the bombing of Auschwitz. Ben Gurion summed up the results of the discussion: "The view of the board is that we should not ask the Allies to bomb places where there are Jews." In the meantime, George Mantello distributed the Auschwitz Protocols (including the Vrba–Wetzler report) and triggered a significant grass roots protest in Switzerland, including Sunday masses, street protests and the Swiss Press Campaign. On 19 June 1944 the Jewish Agency in Jerusalem received the reports summary. David Ben Gurion and the Jewish Agency had reversed its opposition immediately upon learning that Auschwitz was indeed a death camp, and urged U.S. President Franklin Delano Roosevelt to bomb the camp and the train tracks leading to the camp.
Shortly thereafter, Benjamin Akzin, a junior official on the War Refugee Board staff made a similar recommendation. It was put in writing in an inter-office memorandum dated June 29 to his superior, a senior staff member, Lawrence S. Lesser. These recommendations were totally rejected by leading Jewish organizations. On June 28, Lesser met with A. Leon Kubowitzki, the head of the Rescue Department of the World Jewish Congress, who flatly opposed the idea. On July 1, Kubowitzki followed up with a letter to War Refugee Board Director John W. Pehle, recalling his conversation with Lesser and stating:
"The destruction of the death installations can not be done by bombing from the air, as the first victims would be the Jews who are gathered in these camps, and such a bombing would be a welcome pretext for the Germans to assert that their Jewish victims have been massacred not by their killers, but by the Allied bombers."
In June 1944, John Pehle of the War Refugee Board and Benjamin Akzin, a Zionist activist in America, urged the United States Assistant Secretary of War John J. McCloy to bomb the camps. McCloy told his assistant to "kill" the request, as the United States Army Air Forces had decided in February 1944 not to bomb anything "for the purposes of rescuing victims of enemy oppression", but to concentrate on military targets. However, Rubinstein says that Akzin was not involved in discussions between Pehle and McCloy, and that Pehle specifically told McCloy that he was transmitting an idea proposed by others, that he had “several doubts about the matter,” and that he was not “at this point at least, requesting the War Department to take any action on this proposal other than to appropriately explore it.”
On August 2, General Carl Andrew Spaatz, commander of the United States Strategic Air Forces in Europe, expressed sympathy for the idea of bombing Auschwitz. Several times thereafter, in the summer and early autumn of 1944, the War Refugee Board relayed to the War Department suggestions by others that Auschwitz and/or the rail lines could be bombed. It repeatedly noted that it was not endorsing anything. On October 4, 1944, the War Department sent (and only this time) a rescue-oriented bombing proposal to General Spaatz in England for consideration. Although Spaatz’s officers had read Mann’s message reporting acceleration of extermination activities in the camps in Poland, they could perceive no advantage to the victims in smashing the killing machinery, and decided not to bomb Auschwitz. Nor did they seem to understand, despite Mann’s statement that “the Germans are increasing their extermination activities,” that wholesale massacres had already been perpetrated.
Finally, on November 8, 1944 having half-heartedly changed sides, Pehle ordered McCloy to bomb the camp. He said it could help some of the inmates to escape and would be good for the “morale of underground groups.” According to Kai Bird, Nahum Goldmann apparently also changed his mind. Sometime in the autumn of 1944, Goldmann went to see McCloy in his Pentagon office and personally raised the bombing issue with him. However, by November 1944, Auschwitz was more or less completely shut down.
The British Prime Minister, Winston Churchill, did not see bombing as a solution, given that bombers were inaccurate and would also kill prisoners on the ground. The land war would have to be won first. Bombers were used against German cities and to carpet-bomb the front lines. But according to Martin Gilbert Winston Churchill pushed for bombing. Concerning the concentration camps, he wrote to his Foreign Secretary on July 11, 1944: "... all concerned in this crime who may fall into our hands, including the people who only obeyed orders by carrying out these butcheries, should be put to death...." The British Air Ministry was asked to examine the feasibility of bombing the camps and decided not to for "operational reasons," which were not specified in wartime. In August 1944, 60 tons of supplies were flown to assist the uprising in Warsaw and, considering the dropping accuracy at that time, were to be dropped "into the south-west quarter of Warsaw." For various reasons, only seven aircraft reached the city.