Timeline of The Manhattan Project - 1939

1939

• August 2: Albert Einstein signs the Einstein–Szilárd letter, authored by physicist Leó Szilárd and addressed to President Franklin D. Roosevelt, advising him to fund research into the possibility of using nuclear fission as a weapon as Nazi Germany may also be conducting such research.
• September 3: Britain and France declare war on Nazi Germany in response to its invasion of Poland, beginning World War II.
• October 11: Economist Alexander Sachs meets with President Roosevelt and delivers the Einstein-Szilárd letter. Roosevelt authorizes the creation of the Advisory Committee on Uranium.
• October 21: First meeting of the Uranium Committee, headed by Lyman Briggs of the National Bureau of Standards. $6,000 is budgeted for neutron experiments.