Alsos Mission

The Alsos Mission was an organized effort by a team of British and United States military, scientific, and intelligence personnel to discover enemy scientific developments during World War II. Its chief focus was to investigate the progress that Germany was making in the area of nuclear technology, and to seize any German nuclear resources that would either be of use to the Manhattan Project or worth denying to the Soviet Union. It also looked into German chemical and biological weapon development and the means to deliver them, as well as any other advanced Axis technology.

The Alsos Mission was created after the September 1943 Allied invasion of Italy as part of the Manhattan Project's mission to coordinate foreign intelligence related to enemy nuclear activity. The team had a twofold assignment: to search for personnel, records, material, and sites to evaluate these programs and to prevent their capture by the Soviet Union. Alsos personnel followed close behind the front lines in Italy, France, and Germany, sometimes crossing into enemy-held territory to secure valuable resources before they could be destroyed.

The Alsos Mission was commanded by Colonel Boris Pash, a former Manhattan Project security officer, with Samuel Goudsmit as chief scientific advisor. It was jointly staffed by the Office of Naval Intelligence (ONI), the Office of Scientific Research and Development (OSRD), the Manhattan Project, and Army Intelligence (G-2), 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 most of the senior German research personnel into custody, including Otto Hahn, Max von Laue, Werner Heisenberg and Carl Friedrich von Weizsäcker. By November-December 1944, they had concluded that there was no threat of a German atomic bomb, and that the German nuclear program had only reached an experimental phase, not a production phase. After the defeat of Japan, an Alsos mission was sent in to evaluate its nuclear program as well.

Origin

The Manhattan Project was the Allied nuclear weapons program during World War II, led by the United States with help from the United Kingdom and Canada. It was created because scientists, many of whom had fled from Nazi Germany, were worried that Germany might be building an atomic bomb.

After the Allies invaded Italy in September 1943, the Manhattan Project started the Alsos Mission to check on enemy scientific developments, especially Germany’s nuclear research. This small team included military officers, scientists, and intelligence experts. Their job was to find out what the enemy was working on and to make sure important discoveries did not fall into the wrong hands.

Italy

In December 1943, the Alsos Mission traveled to Algiers and then moved on to Italy. There, they met with important leaders and interviewed Italian scientists. They looked at captured documents but found little information about what Germany was doing. By March 1944, most of the team returned to the United States.

Rome was captured on June 4, 1944. The team went back to Italy and secured key places like the University of Rome. They interviewed more scientists and learned that Germany’s nuclear efforts were not very advanced. The mission gathered useful details about German rockets and missiles.

Western Europe

Britain

In December 1943, Groves sent Furman to Britain to discuss setting up a London Liaison Office for the Manhattan Project with the British government. Lieutenant Commander Eric Welsh, the head of the Norwegian Section of MI6, was not impressed with Furman's knowledge of the subject. Groves chose Captain Horace K. Calvert to lead the London Liaison Office. Working with Welsh and Michael Perrin from Tube Alloys, the office interviewed refugee scientists, studied German physics journals, and compiled lists of German scientists and possible nuclear research locations.

France

In August 1944, Pash and a special agent investigated reports that the French physicist Frédéric Joliot-Curie was in Brittany. They found documents at the University of Rennes and later located Joliot-Curie at the Collège de France in Paris. Interviews and documents indicated that German scientists had visited and used facilities there.

Germany

As Allied forces advanced into Germany, Alsos Mission teams searched for nuclear facilities and scientists. They discovered documents and equipment in cities like Strasbourg, Heidelberg, and Göttingen. In April 1945, teams found a nuclear reactor in Haigerloch and captured several key German scientists, including Werner Heisenberg. By the end of the war, the Alsos Mission had gathered significant information about Germany’s nuclear efforts and confirmed that Germany was not close to developing an atomic bomb.

Japan

Plans for the invasion of Japan included an Alsos Mission because of concerns that Japan might use fire balloon attacks together with biological agents. In March 1945, physicist L. Don Leet became head of the scientific section of the Alsos Mission to Japan. Leet's group arrived in Manila in July 1945 and later traveled to Japan after the surrender of Japan. They visited many research places such as Tokyo Imperial University and interviewed over 300 Japanese scientists. They learned about Japan’s work on radar, rockets, and other technologies. Another group from the Manhattan Project, led by Philip Morrison, also came to Japan and found that Japan’s nuclear program had failed mainly because they lacked uranium ore.

Legacy

After visiting the German project at Haigerloch, Goudsmit noted that the German efforts in nuclear technology were much smaller than expected. The facilities were simple and not well-funded compared to the efforts in the United States.

Ultimately, the Alsos Mission did not greatly help the Allies defeat Nazi Germany, as the German nuclear and biological weapons programs were smaller than feared. However, the mission did help gather important scientific knowledge that influenced developments after the war.