1940 - Abraham Lincoln: The War Years by Carl Sandburg
1941 - The Atlantic Migration, 1607-1860 by Marcus Lee Hansen
1942 - Reveille in Washington, 1860-1865 by Margaret Leech
1943 - Paul Revere and the World He Lived In by Esther Forbes
1944 - The Growth of American Thought by Merle Curti
1945 - Unfinished Business by Stephen Bonsal
1946 - The Age of Jackson by Arthur M. Schlesinger, Jr.
1947 - Scientists Against Time by James Phinney Baxter III
1948 - Across the Wide Missouri by Bernard DeVoto
1949 - The Disruption of American Democracy by Roy Franklin Nichols
According to The Pulitzer Prize.