The discovery of nuclear fission by German chemists Otto Hahn and Fritz Strassmann in 1938, and its theoretical … See more

The S-1 Committee meeting on 18 December 1941 was "pervaded by an atmosphere of enthusiasm and urgency" in the wake of the attack on Pearl Harbor and the United States declaration of war on Japan… See more

The Chief of Engineers, Major General Eugene Reybold, selected Colonel James C. Marshall to head the Army's part of the project in June 1942. Marshall created a liaison office in Washington, D.C., but establishe… See more

The day after he took over the project, Groves went to Tennessee with Colonel Marshall to inspect the proposed site there, and Groves was impressed. On 29 September 1942, United States Under Secretary o… See more

The key raw material for the project was uranium, which was used as fuel for the reactors, as feed that was transformed into plutonium, and, in its enriched form, in the atomic bomb itself. There were four known major depo… See more