His best known book is The Impending Crisis, 1848–1861, which was completed and edited by Don E. Fehrenbacher and published posthumously in 1976.
Potter entered graduate school at Yale University the same year, working with Ulrich Bonnell Phillips who died in 1934 before he started his dissertation.
[1] In 1942 Yale published his revised dissertation as Lincoln and His Party in the Secession Crisis and hired him as an assistant professor.
Potter was the Harold Vyvyan Harmsworth Professor of American History at Oxford University in 1947.
[3][4] He posthumously won the 1977 Pulitzer Prize for History for The Impending Crisis, 1848–1861 (1976), an in-depth narrative and analysis of the causes of the American Civil War.