Otto Hahn (8 March 1879 – 28 July 1968) was a German chemist who received the 1944 Nobel Prize in Chemistry for discovering nuclear fission. He is considered a pioneer of radioactivity and radiochemistry. He did not work on Germany's atomic bomb project during World War II, but he was detained with nine other scientists by the Allied Forces. After the war, Hahn reentered academia and research, where he remained until his death. He was also an active opponent of the nuclear arms race between the United States and the Soviet Union.