Operation Paperclip, also known as Project Paperclip, was a joint Office of Strategic Services (OSS) / Strategic Scientific Reserve (SSR) program in which over 1,500 German scientists, technicians, and engineers from Nazi Germany and other foreign countries were brought to the United States of America for employment in the aftermath of World War II.
On May 19, 1945 the United States of America begin Operation Overcast, later renamed Operation Paperclip, an effort to recruit former Nazi scientists to work for the United States as opposed to the Soviet Union. One of the most prominent was former HYDRA scientist Arnim Zola. After joining S.H.I.E.L.D., Zola began to rebuild HYDRA inside S.H.I.E.L.D.
Another recruited scientist, Wernher von Braun, who built the V-2 rockets for the Nazis, now developed rockets that could fly into space. When Peggy Carter came to the Rat prison to interrogate HYDRA general Werner Reinhardt, he expressed his wish to be recruited by the United States government, as many scientists were already recruited. However, because of his numerous war crimes, Carter sentenced him to life imprisonment.