1921 - 1941 By facebooker_2165144867097231 Period: Mar 4, 1921 to Aug 2, 1923 President Warren G. Harding (29th President) Period: Aug 2, 1923 to Mar 4, 1929 President Calvin Coolidge (30th President) May 26, 1924 Immigration Act Jul 2, 1924 Revenue Act Period: Mar 4, 1929 to Mar 4, 1933 President Herbert Hoover (31st President) Jan 23, 1933 20th Amendment Period: Mar 4, 1933 to Apr 12, 1945 President Franklin D. Roosevelt Dec 5, 1933 End of Prohibition Sep 30, 1938 Munich Agreement Period: Sep 1, 1939 to Sep 2, 1945 World War 2 Jul 10, 1940 Battle of Britain Dec 7, 1941 Attack on Pearl Harbor