American President Franklin Delano Roosevelt is one of the most intriguing political figures in world history. He was in office at a time of great change and guided the country through World War II. His policies, which set the nation on a new course, have been discussed and written about in dozens of books. But less attention has been paid to the women in his life, outside of his wife, Eleanor.

One such woman who deserves more scrutiny is FDR’s longtime personal secretary, Marguerite “Missy” LeHand, who sat right outside the Oval Office and was his de facto chief of staff. A new book by Kathryn Smith sheds light on her role in FDR’s life and in the wider theater of politics.

Smith spoke on the Knowledge at Wharton show about what she learned from the careful research she conducted for her book, The Gatekeeper: Missy LeHand, FDR, and the Untold Story of the Partnership That Defined a Presidency .…