'Alsos' was an Allied effort, largely by the USA and UK, planned from a time late in 1943 and implemented around the end of World War II to investigate the German nuclear energy and nuclear weapon programmes, to seize German nuclear resources, materials and personnel to further US research and to prevent their capture by the Soviets, and to establish how far the Germans had gone toward the creation of an atomic weapon (1943/15 October 1945).

The 'Alsos' mission was an organised effort by a team primarily to investigate German scientific developments during World War II, and while its chief focus was on the German nuclear energy project, it also investigated both chemical and biological weapons and the means to deliver them.

'Alsos' was created following the September 1943 Allied 'Avalanche' invasion of Italy with the twin assignments of searching for personnel, records, material and sites for evaluation of German capabilities, and of preventing their seizure by the USSR. It was established as part of the 'Manhattan' Project’s mission to co-ordinate foreign intelligence related to German nuclear activity. 'Alsos' personnel followed close behind the front lines in Italy, France and Germany, occasionally crossing into German-held territory to secure valuable resources before they could be destroyed or the associated scientists escape or fall into Soviet hands.

The 'Alsos' mission was commanded by Colonel Boris T. Pash, a former 'Manhattan' Project security officer, with Samuel Goudsmit as the chief scientific adviser. It was jointly staffed by the Office of Naval Intelligence, the Office of Scientific Research and Development, the 'Manhattan' Project, and US Army intelligence, with field assistance from combat engineers assigned to specific task forces.

'Alsos' teams were successful in locating and removing a substantial portion of the German research effort’s surviving records and equipment. They also took into custody most of the senior German research personnel, including Otto Hahn, Max von Laue, Werner Heisenberg and Carl Friedrich von Weizsäcker.

The 'Manhattan' Project was a research-and-development programmed which operated during and immediately after World War II. Led by the USA with significant contributions principally from the UK and Canada, it was created to produce an atomic bomb. Brigadier General (from 9 March 1944 Major General ) Leslie R. Groves of the US Army Corps of Engineers became its director in September 1942. The project operated in conditions of the utmost secrecy lest its discovery induce the Axis powers, particularly Germany, to accelerate their own nuclear projects or to undertake covert operations against the project.

The 'Manhattan' Project intelligence staff believed that the Japanese atomic programme had not reached any advanced stage as Japan had little access to uranium ore, the industrial effort that was required exceeded Japan’s capacity and, according to US physicists at the University of California, Berkeley, who knew the leading Japanese physicists personally, there were too few Japanese qualified to work in the area. Conversely, German scientists had reputations as leaders in the field, and the fear of Germany developing nuclear weapons first was one of the reasons for the establishment of the 'Manhattan' Project. Adolf Hitler frequently claimed that Germany was developing secret weapons, and it was feared that these might include nuclear weapons. Reports of German nuclear activity were taken seriously, and at the instigation of the 'Manhattan' Project, Norwegian saboteurs and Allied bombers attacked the heavy-water infrastructure in German-occupied Norway late in 1942 and early in 1943.

Following 'Avalanche', Major General Wilhelm D. Styer, the Army Service Forces' chief-of-staff, was concerned that the intelligence activities related to foreign nuclear energy programmes were not being properly co-ordinated, and thus feared that important items might be overlooked unless those responsible were properly briefed. At the same time, however, Styer wished to minimise the number of personnel with access to such secret information. Having the 'Manhattan' Project itself take over responsibility for the co-ordination of these efforts would address both these concerns, and Styer therefore approached Groves on behalf of General George C. Marshall, the US Army chief-of-staff, with that recommendation.

In response, Groves created the 'Alsos' mission as a small joint-services team tasked with the investigation of of Axis scientific developments, including nuclear weapons research. Groves was not happy with the codename, which is the Greek word for 'grove', but decided that any change would only draw unwanted attention.

The Chief of Army Intelligence, Major General George V. Strong, appointed Pash to command the unit. This officer, currently a lieutenant colonel, had served as the head of the Counter Intelligence Branch of the Western Defense Command, where he had investigated suspected Soviet espionage at the Radiation Laboratory at Berkeley. Pash’s command comprised Captain Wayne B. Stanard as his executive officer, four agents of the Counter Intelligence Corps, four interpreters, and four scientists: these last were Dr James B. Fisk from the Bell Telephone Company, Dr John R. Johnson from Cornell University, Commander Bruce Olds from the Office of Naval Intelligence and Massachusetts Institute of Technology and Major William Allis, originally from MIT although then serving on the War Department’s scientific staff.

In December 1943, the 'Alsos' mission reached Algiers, where Pash reported to Major General Walter B. Smith, the chief-of-staff at Allied Force Headquarters, and his chief of intelligence, Brigadier Kenneth Strong. This was awkward as Pash had been instructed that he was not to give the British information about the 'Alsos' mission, but it turned out that Strong was already fully aware of it. It was arranged that Pash would deal with Strong’s US deputy, Colonel Thomas E. Roderick. The 'Alsos' mission then moved to Italy, where it was assigned to Major General Kenyon A. Joyce’s Allied Control Commission. Pash met with Maresciallo d’Italia Pietro Badoglio, the officer who had negotiated Italy’s armistice with the Allies and was now head of the Italian provisional military government. Badoglio gave Patch a letter of introduction addressed to all Italian civil and military authorities.

'Alsos' team members interviewed the Italian minister of communications, the chief of naval ordnance, the staff of the Italian naval academy, and Italian scientists at the University of Naples, and also examined all of the technical documents that could be found. There was little information about developments in northern Italy and Germany. The 'Alsos' mission was attached to Colonel George Smith’s 'S' Force, which was based on a Royal Air Force ground reconnaissance squadron equipped with armoured cars. This unit contained US, British, French and Italian technical specialists of various kinds who entered Rome on the heels of the advancing Allied forces. The expectation that Rome would soon be captured proved premature, and by March 1944 most of the members of the 'Alsos' mission had returned to the USA. The 'Alsos' mission had gathered little of value about nuclear matters, but submitted detailed reports about German rockets and guided missiles.

Rome fell on 4 June 1944, and when the news came of the city’s imminent seizure, Pash was ordered from London to Italy. He flew to Italy and entered the city with 'S' Force on 5 June. Pash took into custody a number of key scientists and arranged for sites targeted by 'Alsos', including the University of Rome and the Consiglio Nazionale delle Ricerche, to be secured. The 'Alsos' mission to Italy was reconstituted under the command of Pash’s deputy, Major Richard C. Ham, and Johnson and Major Robert R. Furman were sent from the USA to join him. The men reached Rome on 19 June, and over the next weeks interviewed scientists including Edoardo Amaldi, Gian-Carlo Wick and Francesco Giordani. The picture which the 'Alsos' mission gained indicated that the German effort was not far advanced.

In December 1943, Groves sent Furman to the UK to discuss with the British the establishment of a London Liaison Office for the 'Manhattan' Project, and to confer over the co-ordination of the intelligence effort. Lieutenant Commander Eric Welsh, the head of the Norwegian Section of MI6, was unimpressed with Furman’s grasp of the subject matter. Groves selected the head of the 'Manhattan' Project’s security activities, Captain Horace K. Calvert, as head of the London Liaison Office, with the title of Assistant Military Attaché. Working in co-operation with Welsh and Michael Perrin from Tube Alloys, the London Liaison Office consisted of Calvert, Captain George B. Davis, two Women’s Army Corps clerks and three agents of the Counter Intelligence Corps.

The London Liaison Office interviewed European refugee scientists and studied German physics journals. It also compiled lists of German scientists of interest and possible locations of nuclear research and industrial facilities, and the mining and stockpiling of uranium and thorium ores. Little thorium was available in Germany or German-occupied Europe, and attention was soon centred on the mines at Joachimsthal in the Sudetenland German-annexed part of Czechoslovakia. Aerial reconnaissance was carried out periodically, and production was measured by assessing the size of the piles of tailings.

Groves warned General Dwight D. Eisenhower that the Germans might attempt to disrupt the 'Overlord' landings in Normandy with radioactive poisons, and sent Major Arthur V. Peterson to brief his chief-of-staff, Lieutenant General Walter B. Smith. Under the codename 'Peppermint', special equipment was prepared and Chemical Warfare Service teams were trained in its use. The British forces made similar preparations for their beaches. The precautions were unnecessary.

Meanwhile, at the urging of Groves and Furman, in March 1944 the new head of the US Department of War General Staff’s assistant chief-of-staff for intelligence, Major General Clayton L. Bissell, decided to create a new and somewhat enlarged 'Alsos' mission for western Europe. Pash assumed command of the new unit upon its official creation by the US Secretary of War, Henry L. Stimson, on 4 April. The military staff members of the new mission were selected by Bissell on Pash’s advice. Lieutenant Colonel George R. Eckman became the deputy commander, and Captain Henry A. Schade was appointed as the head of the naval contingent. Groves and Vannevar Bush, head of the Office of Scientific Research and Development, selected the scientific staff, and appointed as its head Samuel Goudsmit, a University of Michigan physicist with a good command of several western European languages: Goudsmit had not been working on the 'Manhattan' Project, and therefore could not reveal any of its secrets if captured. The British considered creating their own mission, but finally agreed to participate as a junior partner. Three Dutch and one Norwegian officer also served with the 'Alsos' mission which by the end of August had seven officers and 33 scientists.

On 5 August, Pash received a secret message from Washington, DC, to the effect that the French physicist Frédéric Joliot-Curie had been sighted at his holiday home at L’Arcouest in Brittany. Joliot-Curie was at the top of the 'Alsos' mission’s 'wanted list', so Pash and Counter Intelligence Corps Special Agent Gerry Beatson set out to investigate in the wake of Lieutenant General George S. Patton’s advancing US 3^rd Army. On 11 August the two US officers reached the homes of Joliot-Curie, Francis Perrin, and Pierre Auger in the L’Arcouest area. Pash and Beatson arrived during the morning of 17 August with Task Force 'A', and were directed to Joliot-Curie’s house, which had been emptied by the Germans, but the men than searched the University of Rennes and found some documents on 21 August.

The rest of the 'Alsos' mission’s advance party moved to Normandy in August 1944, where it joined 'T' Force, a unit similar to 'S' Force, at Rambouillet, where it was preparing for the liberation of Paris. An 'Alsos' mission team including Pash and Calvert reached Joliot-Curie’s house in the suburbs of Paris on 24 August to find that the French physicist was not there, but at his laboratory at the Collège de France. On the following day the two Americans reached the Porte d’Orléans, where they encountered troops of the French 2ème Division Blindée engaged in liberating the city, and came under small arms fire from the German defenders. The men of the 'Alsos' mission replied with their personal weapons as they made their way through the back streets to the college, where they found Joliot-Curie in his office.

Goudsmit interviewed Joliot-Curie in Paris on 27 August and then, accompanied by Calvert, Joliot-Curie was flown to London where Perrin and Goudsmit interviewed him about the activities of German scientists. Joliot-Curie recalled visits to the Collège de France, which had a cyclotron, by German scientists including Erich Schumann, who had initiated the German nuclear project and controlled it until it was handed to the Reichsforschungsrat (National Research Council) in 1942; by Abraham Esau, who had been in charge of nuclear physics under the Reichsforschungsrat; and by Walter Gerlach, who had replaced him in January 1944. Other German physicists who had used the facilities included Kurt Diebner, Walther Bothe and Erich Bagge, all of whom were known to be associated with the German nuclear project.

Meanwhile, 'T' Force had moved into the Petit Palais. The main body of the 'Alsos' mission soon followed, before opening an office at the Place de l’Opéra. On 5 September, word was received that General Sir Bernard Montgomery’s Anglo-Canadian 21^st Army Group was about to enter Brussels, the capital of Belgium. There were two important 'Alsos' mission objectives in Belgium: the corporate headquarters of Union Minière du Haut Katanga, the world’s largest supplier of uranium ore, in Antwerp, and its uranium processing plant in Olen. A six-man 'Alsos' mission team set out to secure these sites led by Pash and Colonel G. Bryan Conrad, the assistant chief-of-staff for intelligence at European Theater of Operations, United States Army. On reaching Brussels, the team made contact with Lieutenant Colonel David Strangeways, commander of the British 'R' Force, who provided them with an escort of Royal Air Force armoured vehicles. The team reached entered Antwerp on 7 September and found the office of Union Minière, where they learned that more than 1,000 tons of refined uranium had been sent to Germany but also that some 150 tons still remained at Olen. The team set out for Olen, where they located 68 tons, but another 80 tons were missing, having been shipped to France in 1940 ahead of the German invasion of Belgium. The capture of Eindhoven in the Netherlands by the US 101^st Airborne Division allowed early access to another high-priority target, the Philips plant. Brigadier Edgar Williams, the 21^st Army Group’s chief of intelligence, facilitated the 'Alsos' mission’s detour to Eindhoven, where it was able to interview Dutch scientists. Williams also furnished a detachment of Royal Engineers to transport and move the uranium from Olen. Groves had it shipped to England, and then the USA.

The 'Alsos' mission now attempted to recover the shipment that had been sent to France. Documentation indicated that part of it had been sent to Toulouse, and an 'Alsos' mission team under Pash’s command reached Toulouse on 1 October and inspected a French army arsenal. They used a Geiger counter to find barrels containing 31 tons of the uranium from Belgium. Conrad persuaded Major General Frank S. Ross, the Chief of Transportation, Services of Supply, US European Theater of Operations, to release the US 3342^nd Quartermaster Truck Company from the 'Red Ball Express' undertaking to retrieve the shipment. The barrels were collected and transported to Marseille, where they were loaded on a ship bound for the USA. In Marseille, the 'Alsos' mission detachment also met with the detachment that had been sent to Italy, which now rejoined them. The remaining 49 tons of the original shipment to France were never found.

Information gathered in Rennes, Paris and Eindhoven pointed to Strasbourg as a place of particular interest. Physicists Rudolf Fleischmann and Carl Friedrich von Weizsäcker were known to be working at the University of Strasbourg, as was Eugen von Haagen, an expert on viruses whose work was of great concern to the 'Alsos' mission’s biological warfare section. The naval section was interested in the torpedo research being carried out there, and jet engine development was being undertaken at the Junkers-controlled Strasbourg plant.

On 22 November, Lieutenant General Jacob L. Devers’s US 6^th Army Group notified the 'Alsos' mission that the capture of Strasbourg was imminent, and that its should therefore should join 'T' Force in Saarburg, where it was preparing to enter the city. The 'Alsos' mission joined 'T' Force in Strasbourg on 25 November. The German nuclear laboratory was discovered on the grounds of the Strasbourg hospital, where the physicists attempted to pass themselves off as medics. Fleischmann was taken into custody, but von Weizsäcker and von Haagen had fled.

Documents discovered in von Weizsäcker’s office, Fleischmann’s laboratory and Strasbourg hospital indicated that there were nuclear activities at Stadtilm, Haigerloch, Hechingen and Tailfingen. After establishing the 'Alsos' mission’s headquarters in von Haagen’s office, team members found documents concerning secret medical experiments at Natzweiler concentration camp, and also that the Germans had been unable to develop a practical process for uranium enrichment. For the first time the 'Alsos' mission was therefore able to report categorically that the Germans did not have nuclear weapons, and indeed that they would not have them for some time.

When the German 'Nordwind' (iii) offensive threatened Strasbourg, Pash ordered the removal of all captured documents, and the removal or destruction of any documentation indicating the nature of the 'Alsos' mission. Although Strasbourg was not abandoned by the Allies, and ultimately did not fall, the 'Alsos' mission left the city on 8 January 1945. Pash even ordered the preparation of an evacuation plan for the 'Alsos' mission’s main headquarters in Paris. The embarrassing series of intelligence failures that had led to the US Army’s initial reverses in 'Wacht am Rhein' cast doubts on the 'Alsos' mission’s own findings. A four-man team under Eckman was sent to investigate a suspiciously devastating V-2 explosion near Antwerp, and Wardenburg had to confirm that it was not a small nuclear explosion. Rumours that Germany possessed an atomic bomb lasted to a period in March 1945.

A new forward headquarters, 'Alsos' Forward North, was opened at Aachen, and on 8 February the 'Alsos' mission reopened its forward headquarters in Strasbourg as 'Alsos' Forward South. In March, General Omar N. Bradley’s US 12^th Army Group launched its 'Lumberjack' offensive to clear the Germans from the area to the west of the Rhine river. Promoted to colonel on 6 March, Pash led an 'Alsos' mission detachment into Köln on 7 March, but found little additional information.

The interrogation of German prisoners indicated that uranium and thorium were being processed in Germany, mostly at the Auergesellschaft plant at Oranienburg, so Groves arranged for the plant to be bombed on 15 March: a force of 612 Boeing B-17 Flying Fortress heavy bombers dropped 1,500 tons of high explosive bombs and 178 tons of incendiary bombs on the plant.

On 30 March, the 'Alsos' mission reached Heidelberg, where important scientists, including Walther Bothe, Richard Kuhn, Philipp Lenard and Wolfgang Gertner, were captured. Their interrogation revealed that Hahn was at his laboratory in Tailfingen, while Heisenberg and von Laue were at Heisenberg’s laboratory in Hechingen, and the experimental natural uranium reactor that Heisenberg’s team had built in Berlin had been moved to Haigerloch. From this time onward, the primary focus of the 'Alsos' mission was on these nuclear facilities in the Württemberg area.

As the Allied armies moved eastward into Germany during April 1945, 'Alsos' mission teams searched Stadtilm, where they found documentation concerning the German nuclear programme, components of a nuclear reactor, and eight tons of uranium oxide. Scientists captured at Göttingen and Katlenburg-Lindau included Werner Osenberg, head of the planning board of the Reichsforschungsrat, and Fritz Houtermans, who provided information about the Soviet atomic bomb project. At Celle, the 'Alsos' mission uncovered an experimental centrifuge for separating uranium isotopes, the result of work undertaken at the Universität Hamburg by a team under Paul Harteck.

The problem with the targets in the Württemberg area was the fact that they lay not only in the path of the French 1ère Armée’s advance, but were also in the occupation zone allocated to France. Groves attempted to get the occupation boundaries changed, but the Department of State first wished to know the reason, and Groves refused to provide this information. Groves, Marshall and Stimson then decided that the area would have to be secured by US troops who would remove what they could and destroy everything else before handing the area to the French. Pash was sent to ask Devers, commander of the US 6^th Army Group, if the zones of the French 1ère Armée and US 7^th Army could be exchanged, but was told that the matter would have to be taken up with Eisenhower.

Groves now sent Lieutenant Colonel John Lansdale to Europe, where he took part in a meeting with Bedell Smith and Major General Harold R. Bull of SHAEF; Major General Elbridge G. Chapman, the commander of the US 13^th Airborne Division; Pash, Furman, and Goudsmit of 'Alsos'; and Brigadier General Reuben E. Jenkins of the 6^th Army Group. The plan, codenamed 'Effective', called for the 13^th Airborne Division to occupy the area to forestall its capture by the French, and to seize an airfield that could be used to fly in an 'Alsos' mission team, and later to extract it together with captured German scientists. 'Effective' was scheduled for 22 April, and meanwhile Devers took steps to delay the French advance.

The 'Alsos' mission had learned that the uranium ores that had been taken from Belgium in 1944 had been shipped to the Wirtschaftliche Forschungsgesellschaft plant in Stassfurt, which Major General Robert C. Macon’s US 83^rd Division captured on 15 April. As it was in the occupation zone allocated to the USSR at the 'Argonaut' conference in Yalta, the 'Alsos' mission, led by Pash and accompanied by Lansdale, Perrin and Air Commodore Sir Charles Hambro (head of the British 'raw materials mission'), arrived on 17 April to remove anything of interest. In the following 10 days, 260 truckloads of uranium ore, sodium uranate and ferro-uranium weighing about 1,000 tons, were taken away by a US truck company. The uranium was taken to Hildesheim and most of it was flown to the UK in RAF aircraft; the rest had to be moved to Antwerp by train and loaded onto a ship for delivery to England.

On 20 April, the French 1ère Armée captured an intact bridge over the Neckar river at Horb and seized a bridgehead. It was decided to send in a ground force rather than the airborne force planned in 'Effective', which was cancelled on 19 April. On this occasion, instead of following or accompanying the front-line troops, the 'Alsos' mission was to operate behind the German lines. The 'Alsos' mission had received two armoured cars, four Jeeps with machine gun mounts, and two 0.5-in (12.7-mm) heavy machine guns; the other two Jeeps were to carry captured German machine guns. They four armed Jeeps would be accompanied by three unarmed Jeeps. For this 'Big' operation, Pash was to head a special Task Force 'A' built around his 'Alsos' mission team and the US 1269^th Engineer Combat Battalion commanded by Lieutenant Colonel Wilbur White, less its Company B. Hambro decided to accompany the 'Alsos' mission with a British group that included Michael Perrin, David Gattiker, Eric Welsh and Rupert Cecil. Lansdale accompanied Task Force 'A' as Groves’s representative, and Brigadier General Eugene L. Harrison, the 6^th Army Group’s assistant chief-of-staff for intelligence, as Devers’s representative.

The 'Alsos' mission departed on 20 April and linked with the 1269^th Engineer Combat Battalion at Freudenstadt. The intact bridge over the Neckar river at Horb was crossed and Haigerloch was occupied without opposition on 22 April. The main body of Task Force 'A' arrived on the following day. In a laboratory located within a cellar the 'Alsos' mission team discovered a German experimental nuclear reactor shaped like a cylinder and made of graphite blocks, but the uranium and heavy water were missing. The scientists immediately began to dismantle this. Pash left Hambro in charge, while he led troops of Task Force 'A' to Bisingen, and then on to Hechingen, where the Americans captured 25 German scientists including von Weizsäcker, von Laue, Karl Wirtz, Horst Korsching and Bagge. At Tailfingen the Americans seized Hahn and nine members of his staff. At Haigerloch, a sealed drum of documents was retrieved from a cesspool, and three drums of heavy water and 1.5 tons of uranium ingots were found buried in a field. These last were loaded onto trucks. The openings in the cellar were demolished with small charges to prevent their capture by the French.

Heisenberg was still at large as he had left Hechingen on 19 April. On 1 May, Pash set out in pursuit with 10 men in the two armoured cars and two Jeeps. They joined forces with the 36^th Reconnaissance Troop of Major General John E. Dahlquist’s US 36^th Division and entered Urfeld on 2 May, where Pash found Heisenberg at his home. The Americans became involved in firefights with German troops attempting to enter the town, and the 36^th Reconnaissance Troop had to depart on another mission, leaving Pash with just seven men. Fortunately, the German force, which numbered about 700, offered to surrender. Pash returned on 3 May with the 3/142^nd Infantry, which took them prisoner, while Pash and his 'Alsos' mission team took Heisenberg into custody.

By VE-Day, the 'Alsos' mission had a strength of 114 men and women, and was officially disbanded on 15 October 1945.

Another part of the 'Alsos' mission operated in the war against Japan within the US 'Olympic' and 'Coronet' invasion plans of the 'Downfall' scheme. Japanese fire balloon 'bomber' attacks on the USA had aroused fears that the technique might be used in combination with biological agents, with which the Japanese Unit 731 was known to be experimenting. In March 1945, the physicist and seismologist L. Don Leet was appointed as head of the scientific section of the 'Alsos' mission to Japan: he had earlier worked in the 'Manhattan' Project on the 'Trinity' nuclear test in New Mexico. Plans were drawn up to prepare and equip a 'T' Force along the lines of that in Europe, but comprising personnel already in the Pacific theatre. The mission differed from its European counterpart in that it was solely American and consisted of only one intelligence agency. Responsibility for nuclear matters was subsequently handled by a separate 'Manhattan' Project Intelligence Group organised by Groves.

Leet’s group reached Manila in the Philippine islands group during July 1945, and met with the intelligence staff of General Douglas MacArthur’s Army Forces, Pacific. Following the surrender of Japan, the mission travelled to Japan and visited various research establishments including Tokyo Imperial University, Waseda University, Tokyo Institute of Technology, the Institute of Physical and Chemical Research, the Institute for Materials Research, Tokyo Shibaura Denki (Toshiba), the Japan Society for the Promotion of Science, the National Research Council, and the Board of Technology. The mission interviewed more than 300 Japanese scientists and produced reports on Japanese research into radar, rockets and other scientific fields including chemical and biological warfare. The 'Manhattan' Project Intelligence Group, under the command of Philip Morrison, arrived in Japan in September 1945 and, after examining Japan’s nuclear weapons programme, concluded that lack of uranium ore and low priority had doomed the Japanese effort. The group reported that, contrary to US belief, Japan’s nuclear physicists were competent.

In the end, the 'Alsos' mission made little in the way of a real contribution to the Allied defeat of Germany because the German nuclear and biological weapons programmes for which it had been formed to investigate turned out to be smaller and less threatening than had been feared. In the field of nuclear weapons development at least, the underfunded and disorganised German programme lagged far behind the Allies' own efforts. In its appropriation of the accomplishments of European science, the 'Alsos' mission played a small part in the wartime and subsequent scientific and technological developments that characterised and transformed the post-war world.