The Manhattan Project 1942–46

The Manhattan Project was the code name for a US-led research and development project (1942–46), which assembled a team of scientists (many of them, such as Albert Einstein and Enrico Fermi, refugees from fascist regimes) to exploit nuclear fission for military purposes and produce the first atomic bombs. The theoretical physicist Robert Oppenheimer led the project, while Brigadier General Leslie R. Groves oversaw all military activity. The project was initially research-based at the universities of Chicago, Columbia and Berkeley. In December 1942, Fermi and a group of physicists produced the first controlled nuclear chain reaction at the University of Chicago. This prompted the US government to provide substantial further funds to build fission production sites at Oak Ridge, Tennessee, and Hanford, Washington, and a design laboratory in Los Alamos, New Mexico. Uranium mining enterprises were created across the US. The first atomic bomb test was in Alamogordo, New Mexico on 16 July 1945.