Originally known as Operation Overcast, the Operation Paperclip program was established in 1945 and assigned to the newly created Joint Intelligence Objectives Agency (JIOC), which was under the direction of the Office of Strategic Services of the United States. The purpose of the mission was to verify the community of Nazi scientists who had conducted experimentation on German military initiatives. The original idea was that Germany's scientific community had superior technological intelligence and the Western Allies wanted to prevent the information from being distributed through Europe to nations that had been sympathetic to the Fascist cause, including Russia in the looming Cold War.
After initial assessment, the US decided to expand the group to include German engineers and technicians who had been assigned to various locations for field experiments. Germany had recalled many of its technicians and scientists in 1943 to return to a central post with the mission of building more technology. The United States was suspicious that Germany had already shared information with the Japanese military, which could impact the Pacific theatre. US President Harry Truman ordered a total vetting of all German operatives before clearance, looking for anyone who had been an active member of the Nazi Party. The acceptable candidates for relocation in the United States were largely determined after the Osenberg List of German intellectuals was found by the US military.
Those who were approved were given new positions and all traces of their activity within the German military were expunged. Several were questioned extensively over long periods of time before being approved, as the OSS comprised a black list. The Western allies were particularly interested in scientific research in several experimental areas that included electronics, aircraft, chemical, biological and medicinal technology. The United States was particularly interested in the development of infrared technology and had also been suspicious that the Germans had possibly made contact with extraterrestrials, being assisted in aeronautic development. US residency for the intellectuals was established through the embassy located in Mexico as a stealth method of program development.
Operation Paperclip was not fully functional until 1947. The time period leading to full implementation included a program to keep the scientists in Allied-control territory by the Technical Field Information Agency, or FIAT. This agency ceased to exist after the war when Operation Paperclip became official. The agency claimed that the only tangible benefit for the United States entering the war was confiscating the scientific technological advancements that Germany had built prior to and during the Nazi Germany movement across Western Europe.
The 127 rocket scientists were assigned to different US government agencies within their particular specialty and all were offered one-year contracts to work in the United States. The program was an ongoing operation, allowing many of the scientists to establish permanent residence in the United States. At the program's end in 1990 over 1600 European intellectuals had been qualified for relocation in the United States.