Even before the end of World War II, the famous Nazi scientist Wernher von Braun, considered the father of V2 rockets and intercontinental ballistic missiles, negotiated his own surrender to the United States government. Along with more than 500 rocket scientists and researchers, the German was secretly taken to the country, where he received US citizenship. It was called Operation Paperclip, which welcomed more than 1,600 German scientists, engineers and technicians into North American services, including former leaders of the Nazi Party.