In 1939, the President of the USA, FDR, was informed by US intelligence that Germany was on her way to making a nuclear bomb of their own. This led to the creation of the Advisory Committee on Uranium, a team tasked with harnessing and weaponising uranium. Based upon the committees findings, the US started funding research by Enrico Fermi and Leo Szilard, which was focused on uranium enrichment and nuclear chain reactions. The name was changed to the National Defence Research Committee in 1940 and finally the Office of Scientific Research and Development (OSRD) in 1941. In the same year, following the Pearl Harbour attack, the US entered WWII on the side of the Allied powers to fight the Axis. The Army Corps of Engineers merged with the OSRD with FDRs approval, and the project morphed into a military initiative with scientists playing a supporting role. The OSRD created the Manhattan Engineering District in 1942, basing it in NYC U.
S Army Colonel Leslie R. Groves was appointed to lead the project. Fermi and Szilard successfully enriched uranium for the production of uranium-235, for use in the bombs. On December 28th, 1942, FDR approved the formation of the Manhattan project to combine these research efforts with the goal of weaponising nuclear energy. Remote research facilities are set up in Washington, New Mexico and Tennessee as well as sites in Canada, for these tests to be performed. Robert J. Oppenheimer was named Director of the Los Alamos Laboratory in northern New Mexico in 1943. He was already working on the concept of fission energy alongside Edward Teller and others. The Los Alamos Laboratory, the creation of which was named Project Y, was formally established on January 1st, 1943. The complex would be the site of testing of the bombs. On July 26, 1945, in a remote desert location near Alamogordo, NM, the first atomic bom was successfully detonated.