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The ALSOS Missions


Dr. Samuel Goudsmit - Scientific Chief - ALSOS

"On the whole, we gained the definite impression that German scientists did not support their country in the war effort..."  Dr. Samuel Goudsmit - Alsos Scientific Chief - 1945

Col. Boris Pash - Military Chief - No Picture Available

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     From as early as 1939, those "in the know" in the United States worked under the constant fear that Germany might have as much as a two-year lead in the development of a nuclear weapon.  Unless and until the United States had positive knowledge to the contrary, we had to assume that the most competent German scientists and engineers were working on an atomic program with the full capacity of German industry at their disposal.  Anything less would have been derelict.

   Therefore, it was critical to the United States to learn as much as she could about Germany's progress.  However, normal military intelligence channels (G2, ONI, and OSS) seemed inadequate for the following reason: the cloak of secrecy around the Manhattan Project was so complete that military intelligence could not be told anything about atomic energy and thus would not have the information required to be able to analyze German progress.

     The solution presented itself in the fall of 1943 when General Marshall suggested that a separate intelligence operation under the auspices of the Manhattan Engineer District be established.  The following excerpt from a memo by General George Marshall in late 1943 formalized the plan and established the Alsos Missions:

"While the major portion of the enemy's secret scientific developments is being conducted in Germany, it is very likely that much valuable information can be obtained thereon by interviewing prominent Italian scientists in Italy....The scope of inquiry should cover all principal scientific military developments and the investigations should be conducted in a manner to gain knowledge of enemy progress without disclosing our interest in any particular field.  The personnel who undertake this work must be scientifically qualified in every respect....It is proposed to send at the proper time to allied occupied Italy a small group of civilian scientists assisted by the necessary military personnel to conduct these investigations.  Scientific personnel will be selected by Brig. Gen. Leslie R. Groves with the approval of Dr. (Vannevar) Bush and military personnel will be assigned by the Asst. Chief of Staff, G-2, from personnel available to him....This group would form the nucleus for similar activity in other enemy and enemy-occupied countries when circumstances permit."

     The Alsos Missions of the Manhattan Project were conducted in three phases: Phase I - Italy; Phase II - France; and, Phase III - Germany.  In addition there was a headquarters mission established in London.  The original detachment forming the missions consisted of thirteen military personnel, including interpreters and six scientists.  The team members were generally familiar with the research programs of both the United States and Great Britain and were capable of extracting through interrogation and observation detailed scientific information on atomic energy.  From the beginning, Alsos was commanded by Lt. Col. Boris T. Pash.  Eventually Dr. Samuel Goudsmit came aboard as chief of the scientific component.

     MED's London Branch -  In December 1943, a London office was established to act as liaison between the Manhattan Engineer District and various intelligence agencies operating in occupied Europe.  The office was first established by Major R. Furman and later placed under the command of Captain Horace K. Calvert.  Maj. Furman returned to Washington to act as the point man for General Groves.  In addition to Calvert, the office was comprised of a Capt. George C. Davis, three WAC's and two counterintelligence agents.  The primary purpose of this liaison office was to pave the road for the three Alsos Missions by locating up to fifty German nuclear scientists and any laboratories that they were suspected of using for atomic research.

     By the time the second Alsos mission into occupied France was organized, Horace Calvert had succeeded in obtaining dossiers on all of the top German scientists, where they worked and where they lived.

     Alsos I - Italy -  The objectives of Alsos in Italy were to obtain advance information regarding scientific developments in enemy research and development and to secure all important persons, laboratories, and scientific information immediately upon their becoming available.

     The Italian Mission was first assembled in Algiers on December 14, 1943.  In addition to Lt. Col. Boris Pash, there was an executive officer, four interpreters, four CIC agents and four scientists: Maj. William Allis, Lt. Cdr. Bruce S. Old, Dr. James B. Fisk (OSRD) and Dr. John R. Johnson (also from the OSRD). 

     While on the ground in Italy, the mission was unable to obtain any conclusive information about Germany's experimentation with atomic energy, but several other scientific-type discoveries were of significant use to the Allies.

     Alsos II - France -  By the summer of 1944, the Alsos contingents had grown to seven operations officers and thirty-three scientists, most of whom were commissioned officers.  On August 9, 1944, advance elements of the Alsos mission landed in occupied France and entered the city of Rennes.  Later in the month, Col. Pash, Captain Calvert and two other counterintelligence agents joined the leading units of the Twelfth Army as it advanced toward Paris.  In fact, Pash's Jeep was the second vehicle to enter Paris.

     One of the primary objectives of the Alsos II mission was the College of France in Paris where Frederic Joliot-Curie had his laboratory.  Although Joliot willingly assisted his interrogators, many felt that he couldn't be trusted...entirely.  He did however confirm that it was his belief that the German's had "made little progress" toward harnessing atomic energy.  Perhaps the most important information to come out of the Joliot interviews were the names of several important German scientists who had either visited or temporarily worked at Joliot's laboratory.  Those mentioned were Professor Erich Schumann, who once headed German research on uranium; Dr. Kurt Diebner, a nuclear physicist; Professor Walter Bothe, an outstanding German nuclear experimentalist; Dr. Abraham Essau, Dr. Wolfgang Gertner, Dr. Erich Bagge, and Dr. Werner Maurer. 

     By early fall, Paris was firmly in the hands of the Allies and the Alsos II mission established a headquarters there.  From this headquarters several smaller Alsos teams worked with the advancing armies to begin the awesome task of searching for the German scientists, capturing any nuclear related materials such as uranium and heavy water, and locating and deciphering any related scientific documents.  The most difficult task would be locating the German scientists and their laboratories, although Calvert's "road map" from the London office helped immensely. 

     During the latter months of 1944, as the Alsos mission advanced toward Germany, progress was temporarily halted by the German counter-offensive (Battle of the Bulge).  The mission used this time to analyze the thousands of pieces of information that had come into their possession.  Persistent references to a small German community of Hechingen gave rise to the belief that some type of nuclear research may be centered there...however, the whereabouts of three of the most prominent of the German physicists, Werner Heisenberg, Otto Hahn and Carl von Weizacker, were still unknown.

     Alsos III - Germany -  The Alsos III mission entered Germany on February 24, 1945.  However, now an additional urgency occupied much of their time.  None of Germany's nuclear materials and absolutely none of the German scientists must be allowed to fall into Russia's hands.  This new element was the source of much intrigue as the Allies advanced toward Berlin.  For instance, one key German facility lay square within the planned Russian zone.  There was no way that the Americans could reach the facility first so General Groves made a request to General Marshall to have it destroyed.  On March 15th, 612 Flying Fortresses of the 8th Air Force dropped close to 2,000 tons of high explosives on the Auergesellschaft Works in Oranienburg just to the north of Berlin.  The plant was totally destroyed.

     Further intrigue ensued with a little known tactical Alsos mission labeled Operation Harborage.  After France fell to the Allies, it was decided to give the French a "zone of occupation" in Germany when they finally surrendered.  The zone given to the French was originally designated as an American zone.  A few suspected nuclear research facilities, including the research center reputed to be in the Hechingen area was in the planned French zone.  General Groves states: " As I saw it, there could be no question but that American troops must be the first to arrive at this vital installation, for it was of the utmost importance to the United States that we control the entire area that contained the German atomic energy activities...I was forced to initiate some drastic measures to accomplish our purpose."

     The strategy behind Operation Harborage was to have a sizeable force, perhaps at the Corps level, cut diagonally across in front of the advancing French army and seize the area long enough to capture the people we wanted, seize and remove all available records, and destroy any remaining facilities.  The operation was initiated in April 1945 and Hechingen was captured on April 24th.  Col. Pash seized a large atomic physics laboratory and took into custody several sought-after scientists including Otto Hahn, Carl von Weizacker, and Max von Laue.  It was learned that Heisenberg, Gerlach, and a few others had left Hechingen two weeks prior and were possibly in Munich or at Urfeld in the Bavarian Alps.  On the 27th, the German scientists were transferred to Heidelberg for further questioning, where information on the whereabouts of German atomic research records were revealed by von Weizacker.  They were sealed in a metal drum which was stored in a cesspool in back of von Weizacker's house.

     At about the time that Operation Harborage was under way, the continuing investigations at the Alsos Forward Headquarters at Heidelberg were bearing fruit.  It was becoming apparent that there were two groups in Germany working on the uranium pile, the first under Kurt Diebner at Frankfurt and the second under Werner Heisenberg.  On April 12th, Diebner's laboratory was seized in Frankfurt.  On May 1, 1945, Gerlach was captured and Diebner was picked up on the 3rd.  Simultaneously, an operation led by Pash at Urfeld, captured Heisenberg and quickly removed him along with confiscated records to Heidelberg. 

     One other major accomplishment of Alsos III was an operation headed up by Lansdale into an area near Stassfurt, Germany.  After seizing a salt mine known as the WIFO plant, Lansdale and his men discovered an inventory of close to 1100 tons of uranium ore.  This discovery prompted the following memo from General Groves, head of the Manhattan Engineer District, to General George Marshall, Chief of Staff:  "In 1940 the German army in Belgium confiscated and removed to Germany about 1200 tons of uranium ore.  So long as this material remained hidden under the control of the enemy, we could not be sure but that he might be preparing to use atomic weapons.  Yesterday I was notified by cable that personnel of my office had located this material near Stassfurt, Germany, and that it was now being removed to a safe place outside Germany where it would be under the complete control of American and British authorities.  The capture of this material, which was the bulk of uranium supplies available in Europe, would seem to remove definitely any possibility of the Germans making any use of an atomic bomb in this war."

     The three Alsos missions into occupied Europe were a little known yet eminently successful operation of the Manhattan Engineer District.  At the end of the war in Europe there were 114 men and women with Alsos comprised of 28 officers, 43 enlisted men, 19 scientists, 5 civilian employees and 19 CIC agents.  The mission was officially disbanded on October 15, 1945.

     Furthermore, all of the key German scientists captured and interrogated by Alsos were relocated to Farm Hall, a country estate in England where their every word was surreptitiously recorded by the British.  One interesting dialogue follows:

Diebner:  "I wonder whether there are microphones installed here?"

Heisenberg:  "Microphones installed? (Laughter)  Oh, no, they're not as cute as all that.  I don't think they know the real Gestapo methods; they're a bit old-fashioned in that respect."

Web Master's Note:  Much of the factual information above and the selected quotations were taken from the book "Now It Can Be Told", by General Leslie M. Groves - Harper, 1962.  Groves devotes several chapters to the Alsos Missions and we recommend this book highly to anyone wishing to learn more about this fascinating story as well as those desiring to gain a broad insight into the workings of the Manhattan Project.  "Click" here if you wish to purchase this book from Amazon

February 2002




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