Friedrich Wilhelm Strassmann was a German chemist who, with Otto Hahn in December 1938, identified the element barium as a product of the bombardment of uranium with neutrons. Their observation was the key piece of evidence necessary to identify the previously unknown phenomenon of nuclear fission, as was subsequently recognized and published by Lise Meitner and Otto Frisch. In their second publication on nuclear fission in February 1939, Strassmann and Hahn predicted the existence and liberation of additional neutrons during the fission process, opening up the possibility of a nuclear chain reaction.

Otto Hahn was a German chemist who was a pioneer in the fields of radioactivity and radiochemistry. He is referred to as the father of nuclear chemistry and father of nuclear fission. Hahn and Lise Meitner discovered radioactive isotopes of radium, thorium, protactinium and uranium. He also discovered the phenomena of atomic recoil and nuclear isomerism, and pioneered rubidium–strontium dating. In 1938, Hahn, Meitner and Fritz Strassmann discovered nuclear fission, for which Hahn alone, was awarded the 1944 Nobel Prize for Chemistry. Nuclear fission was the basis for nuclear reactors and nuclear weapons.