Dr. Wernher Magnus Maximilian Freiherr von Braun (March 23, 1912 – June 16, 1977) was one of the leading figures in the development of rocket technology in Germany and the United States. The German scientist who led Germany's rocket development program before and during World War II, entered the United States at the end of the war through the then-secret Operation Paperclip. He became a naturalized U.S. citizen and worked on the American ICBM program before joining NASA, where he served as Director. He is generally regarded as the father of the United States space program.