Clement Attlee was Prime Minister of the United Kingdom from 1945-1951. Clement Attlee succeeded Winston Churchill, and was present at the final allied war conference in Potsdam, Germany, in August 1945, and worked during his term to solidify relations with the U.S. Prior to serving as Prime Minister, Attlee was Mayor of Stepney, England, 1919-1922; Member of Parliament, 1922-1924; Undersecretary of State for War, 1924-1929; and Chancellor of the Duchy of Lancaster, Postmaster General, 1929-1931.